Merge remote-tracking branch 'origin/master' into worktree/custom-deepseek-models

# Conflicts: # packages/host/apiproxy/README.i18n.yaml
2026-07-31 14:48:50 +08:00
parent ef996473a7 5dcb096015
commit 267fbdbf7f
113 changed files with 1614 additions and 278 deletions
--- a/packages/client/connection/src/client/fixture.ts
+++ b/packages/client/connection/src/client/fixture.ts
@@ -969,6 +969,9 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
    updatedAt: fixtureEpoch,
  }]
  let nextWorkspace = 1
+  // Registry-global archive set mirroring the host: archived sessions keep
+  // their workspace accounting slot and only grouping surfaces hide them.
+  const archivedSessionIds: SessionId[] = []

  // In-memory browse tree behind the fixture's `browse` picker capability —
  // deterministic content mirroring the design mock so assembled Web tests
@@ -1623,7 +1626,10 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
      openPath: request => ok(request, { opened: true as const }),
    },
    workspace: {
-      list: request => ok(request, { items: workspaces.map(w => ({ ...w })) }),
+      list: request => ok(request, {
+        items: workspaces.map(w => ({ ...w })),
+        archivedSessionIds: [...archivedSessionIds],
+      }),
      create: (request) => {
        const { path, name } = request.payload
        const target = path ?? `/tmp/fixture-workspaces/${name ?? ''}`
@@ -1709,6 +1715,16 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
        }
        return ok(request, { workspace: { ...workspace } })
      },
+      archiveSession: (request) => {
+        const missing = requireSession(request)
+        if (missing !== undefined) return missing
+        const { sessionId } = request.payload
+        if (!archivedSessionIds.includes(sessionId)) {
+          archivedSessionIds.push(sessionId)
+          emitHost({ type: 'host/archived-sessions-changed', archivedSessionIds: [...archivedSessionIds] })
+        }
+        return ok(request, { archivedSessionIds: [...archivedSessionIds] })
+      },
    },
    commands: {
      // The catalog mirrors one session's effective view (every fixture
@@ -2089,6 +2105,7 @@ export class FixtureApiClient extends AbstractApiClient {
      case 'workspace.rename': return this.api.workspace.rename(request)
      case 'workspace.delete': return this.api.workspace.delete(request)
      case 'workspace.insertSessionBefore': return this.api.workspace.insertSessionBefore(request)
+      case 'workspace.archiveSession': return this.api.workspace.archiveSession(request)
      case 'command.list': return this.api.commands.list(request)
      case 'command.execute': return this.api.commands.execute(request, signal)
      case 'skill.list': return this.api.skills.list(request)
--- a/packages/client/connection/tests/fake-api.ts
+++ b/packages/client/connection/tests/fake-api.ts
@@ -122,7 +122,7 @@ export class FakeApiClient implements IApiClient {
  }

  readonly workspace: IApiClient['workspace'] = {
-    list: (payload: unknown) => this.record('workspace.list', payload, Promise.resolve(ok({ items: [] }))),
+    list: (payload: unknown) => this.record('workspace.list', payload, Promise.resolve(ok({ items: [], archivedSessionIds: [] }))),
    create: (payload: unknown) => this.record('workspace.create', payload, Promise.resolve(ok({
      workspace: { workspaceId: 'fk-ws' as never, path: '/f/ws', title: 'ws', sessionIds: [], createdAt: '0', updatedAt: '0' },
      created: true,
@@ -134,6 +134,9 @@ export class FakeApiClient implements IApiClient {
    insertSessionBefore: (payload: unknown) => this.record('workspace.insertSessionBefore', payload, Promise.resolve(ok({
      workspace: { workspaceId: 'fk-ws' as never, path: '/f/ws', title: 'ws', sessionIds: [], createdAt: '0', updatedAt: '0' },
    }))),
+    archiveSession: (payload: unknown) => this.record('workspace.archiveSession', payload, Promise.resolve(ok({
+      archivedSessionIds: [(payload as { sessionId: SessionId }).sessionId],
+    }))),
  }

  // Payloads stay `unknown` (lint-lane note above); response rows are the real
--- a/packages/client/locale/tests/language-row.spec.tsx
+++ b/packages/client/locale/tests/language-row.spec.tsx
@@ -21,7 +21,7 @@ function emptySessions() {
 }
 function emptyWorkspaces() {
  const store = createSnapshotStore<WorkspaceListState>({
-    items: [], state: 'idle', phase: 'ready', error: null,
+    items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
    baselinesReady: true, recentWorkspaceId: undefined,
  })
  return bindSnapshotSelector(store)
--- a/packages/client/runtime/README.i18n.yaml
+++ b/packages/client/runtime/README.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/client/runtime/README.md
-README.md: 9f2b165f1a98dcecfa3ab82386da9b094cfd2f54
-README.zh.md: 3ed047e65d3bddc14c3b6b84f327bbeebf805d4b
+README.md: 022dc6f82ea7aa1490144449ea61a84a512906a2
+README.zh.md: 4d0f74f573a5e03b05755cfcfea930e69ef386e2
--- a/packages/client/runtime/README.md
+++ b/packages/client/runtime/README.md
@@ -10,6 +10,8 @@ Workspace and Session lists have independent monotone `pending` → `ready` base

 `WorkspacesService.delete(workspaceId)` removes the registration from the client projection after the successful unary response; the matching `host/workspace-removed` frame is idempotent and synchronizes other tabs. Session state and the current Session selection are independent, so accounted Sessions immediately project under Ungrouped after their Workspace disappears.

+`WorkspaceListState.archivedSessionIds` mirrors the Host's registry-global archive set (a `readonly SessionId[]` in Host order, replaced only when membership changes; consumers needing O(1) lookups build a transient Set). It is full-snapshot state: the `workspace.list` baseline, the `archiveSession` unary echo, and the `host/archived-sessions-changed` frame each install the complete set. `WorkspacesService.archiveSession(sessionId)` archives over the wire; the projection sweep clears the current selection into the New Session view state whenever it lands in the archive set — one rule covering the local echo, another tab's frame, and a reconnect baseline restoring a selection archived while this client was away. A set installed while a `workspace.list` request is in flight also supersedes that stale baseline's set. Grouping surfaces hide members everywhere while the session rows stay in the list store.
+
 SlotsService gives the renderer separate bare observables for `useSessions` and `useWorkspaces`; web-react creates the hooks. Workspace business state does not enter `SessionListState` or an entry store.

 `SessionsService.search(query, signal)` is a stateless one-shot action over the `session.search` RPC. It returns ranked session/snippet pairs without putting query, loading, or error state into the shared Session list, so each UI owner controls debounce, cancellation, stale-response suppression, and fallback presentation. `searchResultLimit` re-exposes `SESSION_SEARCH_RESULT_LIMIT` — the bound the response schema itself enforces — as injected presentation data, so client plugins do not duplicate it. It is a protocol constant rather than per-connection state, so the connection handle does not carry it.
--- a/packages/client/runtime/README.zh.md
+++ b/packages/client/runtime/README.zh.md
@@ -10,6 +10,8 @@ Workspace 和 Session 列表各自具有单调的 `pending` → `ready` 基线

 `WorkspacesService.delete(workspaceId)` 在一元响应成功后从客户端投影中移除注册记录；对应的 `host/workspace-removed` 帧具有幂等性，并负责同步其他标签页。Session 状态与当前 Session selection 相互独立，因此 Workspace 消失后，其已纳入客户端投影的 Session 会立即投影到 Ungrouped 下。

+`WorkspaceListState.archivedSessionIds` 镜像 Host 的注册表级全局归档集合（一个按 Host 顺序的 `readonly SessionId[]`，仅在成员变化时才替换；需要 O(1) 查询的消费方自建临时 Set）。它是全快照状态：`workspace.list` 基线、`archiveSession` 一元回声和 `host/archived-sessions-changed` 帧各自安装完整集合。`WorkspacesService.archiveSession(sessionId)` 通过 wire 归档；投影层在当前 selection 落入归档集合时统一清空为 New Session 视图状态——一条规则同时覆盖本地回声、其他标签页的帧、以及重连基线恢复出一个离线期间被归档的 selection。在 `workspace.list` 请求进行中安装的集合还会取代该过期基线携带的集合。各分组视图在所有位置隐藏集合成员，而会话行本身仍留在列表 store 中。
+
 SlotsService 分别为 renderer 提供 `useSessions` 与 `useWorkspaces` 的裸 observable；web-react 创建钩子。Workspace 业务状态不会进入 `SessionListState` 或配置项 store。

 `SessionsService.search(query, signal)` 是基于 `session.search` RPC 的无状态单次操作。它返回经过排序的会话／snippet 对，但不会将查询条件、加载状态或错误状态写入共享 Session 列表，因此每个 UI 所有者都自行负责防抖、取消、抑制陈旧响应和回退呈现。`searchResultLimit` 将 `SESSION_SEARCH_RESULT_LIMIT`——即响应 schema 自身强制执行的上限——作为注入的呈现数据重新公开，使客户端插件无需复制该值。它是协议常量而非逐连接状态，因此连接 handle 不携带它。
--- a/packages/client/runtime/src/client/contract/workspaces.ts
+++ b/packages/client/runtime/src/client/contract/workspaces.ts
@@ -76,4 +76,11 @@ export interface IWorkspaces {
   * @returns the updated Workspace view.
   */
  insertSessionBefore(workspaceId: WorkspaceId, sessionId: SessionId, beforeSessionId?: SessionId): Promise<WorkspaceView>
+  /**
+   * Archive a session into the registry-global set (hidden from grouping
+   * surfaces; session log and accounting slot remain). Archiving the current
+   * session clears the selection into the New Session view state.
+   * @param sessionId - session to archive.
+   */
+  archiveSession(sessionId: SessionId): Promise<void>
 }
--- a/packages/client/runtime/src/client/workspaces/manager.ts
+++ b/packages/client/runtime/src/client/workspaces/manager.ts
@@ -14,6 +14,14 @@ export type WorkspaceListPhase = 'pending' | 'ready'
 /** Immutable workspace-list snapshot. */
 export interface WorkspaceListSnapshot {
  items: readonly WorkspaceView[]
+  /**
+   * Registry-global archive set in Host order (hidden from grouping
+   * surfaces; accounting slots retained). A plain array, not a Set: public
+   * snapshot state stays in the store engine's plain-data vocabulary
+   * (immer drafts reject Sets without the MapSet plugin); membership
+   * lookups build their own transient Set where they need one.
+   */
+  archivedSessionIds: readonly SessionId[]
  state: 'idle' | 'loading' | 'error'
  phase: WorkspaceListPhase
  error: RpcError | null
@@ -28,11 +36,21 @@ export class WorkspaceManager {
  private items: Workspace[] = []
  private itemViewsSource: readonly Workspace[] | null = null
  private itemViewsCache: readonly WorkspaceView[] = []
+  // Full-snapshot state (list response / unary response / changed frame all
+  // carry the complete set), so deltas never merge — installs replace.
+  private archivedSessionIds: readonly SessionId[] = []
  private state: WorkspaceListSnapshot['state'] = 'idle'
  private phase: WorkspaceListPhase = 'pending'
  private error: RpcError | null = null
  private inflight: Promise<void> | null = null
  private refreshFrames: WorkspaceDelta[] | null = null
+  /**
+   * True once a frame or unary echo installed the archive set while a list
+   * request was in flight: that install is newer than the pending baseline,
+   * so the baseline's (older) set must not roll it back — the archive
+   * mirror of replaying refreshFrames over the item baseline.
+   */
+  private archivedSupersedesRefresh = false
  /**
   * Ids this process has seen removed, kept for the connection's lifetime so
   * a late changed frame or a stale baseline row cannot resurrect a deleted
@@ -77,6 +95,7 @@ export class WorkspaceManager {
          items = items.filter(workspace => !this.removedIds.has(workspace.workspaceId))
          for (const delta of frames) items = applyWorkspaceDelta(items, delta)
          this.installViews(items)
+          if (!this.archivedSupersedesRefresh) this.installArchived(result.value.archivedSessionIds)
          this.state = 'idle'
          this.phase = 'ready'
        } else {
@@ -90,6 +109,7 @@ export class WorkspaceManager {
        this.error = folded.ok ? null : folded.error
      } finally {
        this.refreshFrames = null
+        this.archivedSupersedesRefresh = false
        this.inflight = null
        this.notifier.markDirty()
      }
@@ -158,6 +178,18 @@ export class WorkspaceManager {
    return result
  }

+  /**
+   * Archive one session in the registry-global set, then install the
+   * returned full set without waiting for the changed frame.
+   * @param sessionId - session to archive.
+   * @returns the wire result.
+   */
+  async archiveSession(sessionId: SessionId): Promise<RpcResult<{ archivedSessionIds: SessionId[] }>> {
+    const { result } = await this.api.workspace.archiveSession({ sessionId })
+    if (result.ok) this.installArchived(result.value.archivedSessionIds)
+    return result
+  }
+
  /**
   * Host-frame entry. Non-workspace frames are ignored so the runtime can
   * fan one host stream out to both object managers.
@@ -166,6 +198,9 @@ export class WorkspaceManager {
  handleHostEnvelope(envelope: RpcRequest<HostFrame>): void {
    if (envelope.payload.type === 'host/workspace-changed') this.upsert(envelope.payload.workspace)
    else if (envelope.payload.type === 'host/workspace-removed') this.remove(envelope.payload.workspaceId)
+    else if (envelope.payload.type === 'host/archived-sessions-changed') {
+      this.installArchived(envelope.payload.archivedSessionIds)
+    }
  }

  /** Re-pull the baseline after each connection generation. */
@@ -194,12 +229,26 @@ export class WorkspaceManager {
  private buildSnapshot(): WorkspaceListSnapshot {
    return {
      items: this.itemViews(),
+      archivedSessionIds: this.archivedSessionIds,
      state: this.state,
      phase: this.phase,
      error: this.error,
    }
  }

+  /**
+   * Replace the archive set when membership actually changed (array identity
+   * backs Object.is short-circuits). Host snapshots are append-ordered, so
+   * positional comparison is exact, not merely heuristic.
+   */
+  private installArchived(archivedSessionIds: readonly SessionId[]): void {
+    if (this.refreshFrames !== null) this.archivedSupersedesRefresh = true
+    if (archivedSessionIds.length === this.archivedSessionIds.length
+      && archivedSessionIds.every((id, index) => id === this.archivedSessionIds[index])) return
+    this.archivedSessionIds = [...archivedSessionIds]
+    this.notifier.markDirty()
+  }
+
  /** Upsert one Host view, optionally retaining the local object that materialized it. */
  private upsert(view: WorkspaceView, identity?: Workspace): void {
    if (this.removedIds.has(view.workspaceId)) return
--- a/packages/client/runtime/src/client/workspaces/service.ts
+++ b/packages/client/runtime/src/client/workspaces/service.ts
@@ -14,6 +14,14 @@ import { WorkspaceManager, type WorkspaceListPhase } from './manager.ts'
 /** Workspace list plus the two-baseline readiness and default-target projection. */
 export interface WorkspaceListState {
  items: readonly WorkspaceView[]
+  /**
+   * Registry-global archive set in Host order: grouping surfaces hide these
+   * sessions everywhere (workspace groups and the ungrouped bucket) while
+   * their session logs and workspace accounting slots remain. A plain array
+   * (store-engine vocabulary; immer drafts reject Sets) — membership lookups
+   * build their own transient Set.
+   */
+  archivedSessionIds: readonly SessionId[]
  state: 'idle' | 'loading' | 'error'
  phase: WorkspaceListPhase
  error: RpcError | null
@@ -58,7 +66,7 @@ export class WorkspacesService implements IWorkspaces {
  constructor(ctx: Context, private readonly api: IApiClient, private readonly sessions: SessionsPort) {
    this.manager = new WorkspaceManager(api)
    this.list = createSnapshotStore<WorkspaceListState>({
-      items: [], state: 'idle', phase: 'pending', error: null,
+      items: [], archivedSessionIds: [], state: 'idle', phase: 'pending', error: null,
      baselinesReady: false, recentWorkspaceId: undefined,
    })
    this.manager.subscribe(() => { this.project() })
@@ -88,10 +96,14 @@ export class WorkspacesService implements IWorkspaces {
    if (inflight !== undefined) return inflight
    // Reuse: blank && same canonical cwd (workspace.path is the host realpath
    // canon; summary cwd is the session header passthrough of the same canon).
+    // An archived blank is never reused: reuse would open a session no
+    // grouping surface can show, so New Session mints a fresh one instead.
+    const archived = this.list.getSnapshot().archivedSessionIds
    const sessions = this.sessions.list.getSnapshot()
    for (const id of sessions.ids) {
      const summary = sessions.byId[id]
-      if (summary !== undefined && summary.blank && summary.cwd === workspace.path) return summary.id
+      if (summary !== undefined && summary.blank && summary.cwd === workspace.path
+        && !archived.includes(summary.id)) return summary.id
    }
    const attempt = this.sessions.create({ workspaceId })
      .finally(() => { this.connecting.delete(workspaceId) })
@@ -249,6 +261,17 @@ export class WorkspacesService implements IWorkspaces {
    if (!result.ok) throw new Error(`workspace delete failed: ${result.error.code}: ${result.error.message}`)
  }

+  /**
+   * Archive a session into the registry-global set. Clearing an archived
+   * current selection is the projection sweep's job (one rule for the local
+   * echo and a remote tab's frame alike).
+   * @param sessionId - session to archive.
+   */
+  async archiveSession(sessionId: SessionId): Promise<void> {
+    const result = await this.manager.archiveSession(sessionId)
+    if (!result.ok) throw new Error(`session archive failed: ${result.error.code}: ${result.error.message}`)
+  }
+
  /**
   * Move a session within its Workspace's manual order (DOM-insertBefore-like).
   * @param workspaceId - owning workspace.
@@ -291,8 +314,17 @@ export class WorkspacesService implements IWorkspaces {
    const workspace = this.manager.getSnapshot()
    const sessions = this.sessions.list.getSnapshot()
    const baselinesReady = workspace.phase === 'ready' && sessions.phase === 'ready'
+    // An archived current selection clears into the New Session view state —
+    // a hidden row must not stay open behind the list. Sweeping here covers
+    // every install path with one rule: the local unary echo, another tab's
+    // changed frame, and a reconnect baseline restoring a persisted
+    // selection that was archived while this client was away.
+    if (sessions.current !== undefined && workspace.archivedSessionIds.includes(sessions.current)) {
+      this.sessions.clear()
+    }
    this.list.set({
      items: workspace.items,
+      archivedSessionIds: workspace.archivedSessionIds,
      state: workspace.state,
      phase: workspace.phase,
      error: workspace.error,
--- a/packages/client/runtime/tests/fake-api.ts
+++ b/packages/client/runtime/tests/fake-api.ts
@@ -140,7 +140,10 @@ export class FakeApiClient implements IApiClient {
    openPath: (payload: unknown) => this.record('host.openPath', payload, this.onOpenPath(payload)),
  }

-  onWorkspaceList: (payload: unknown) => Promise<RpcResponse<{ items: never[] }>> = () => Promise.resolve(ok({ items: [] }))
+  // The archive-set field defaults at the binding below so list stubs keep
+  // the pre-archive `{ items }` shape; a stub carrying the field wins.
+  onWorkspaceList: (payload: unknown) => Promise<RpcResponse<{ items: never[]; archivedSessionIds?: never[] }>> =
+    () => Promise.resolve(ok({ items: [] }))
  onWorkspaceCreate: (payload: unknown) => Promise<RpcResponse<{ workspace: WorkspaceView; created: boolean }>> =
    () => Promise.resolve(ok({ workspace: fakeWorkspace('fk-ws'), created: true }))

@@ -153,13 +156,22 @@ export class FakeApiClient implements IApiClient {
  onWorkspaceInsertSessionBefore: (payload: unknown) => Promise<RpcResponse<{ workspace: WorkspaceView }>> =
    () => Promise.resolve(ok({ workspace: fakeWorkspace('fk-ws') }))

+  onWorkspaceArchiveSession: (payload: unknown) => Promise<RpcResponse<{ archivedSessionIds: SessionId[] }>> =
+    payload => Promise.resolve(ok({ archivedSessionIds: [(payload as { sessionId: SessionId }).sessionId] }))
+
  readonly workspace: IApiClient['workspace'] = {
-    list: (payload: unknown) => this.record('workspace.list', payload, this.onWorkspaceList(payload)),
+    list: (payload: unknown) => this.record('workspace.list', payload, this.onWorkspaceList(payload).then(response => (
+      response.result.ok
+        ? { ...response, result: { ok: true as const, value: { archivedSessionIds: [] as never[], ...response.result.value } } }
+        : response
+    )) as ReturnType<IApiClient['workspace']['list']>),
    create: (payload: unknown) => this.record('workspace.create', payload, this.onWorkspaceCreate(payload)),
    rename: (payload: unknown) => this.record('workspace.rename', payload, this.onWorkspaceRename(payload)),
    delete: (payload: unknown) => this.record('workspace.delete', payload, this.onWorkspaceDelete(payload)),
    insertSessionBefore: (payload: unknown) =>
      this.record('workspace.insertSessionBefore', payload, this.onWorkspaceInsertSessionBefore(payload)),
+    archiveSession: (payload: unknown) =>
+      this.record('workspace.archiveSession', payload, this.onWorkspaceArchiveSession(payload)),
  }

  // Payloads stay `unknown` (lint-lane note above); response rows are the real
--- a/packages/client/runtime/tests/workspaces-service.spec.ts
+++ b/packages/client/runtime/tests/workspaces-service.spec.ts
@@ -183,6 +183,12 @@ describe('WorkspacesService', () => {

    // Unknown workspace fails loud instead of silently creating in nowhere.
    await expect(workspaces.connectWorkspace(wid('ghost'))).rejects.toThrow(/unknown workspace ghost/)
+
+    // An archived blank is never reused: no surface can show it, so New
+    // Session mints a fresh one for alpha instead.
+    await workspaces.archiveSession(sid('s-blank'))
+    api.onCreate = () => Promise.resolve(ok({ sessionId: sid('s-fresh-2') }))
+    await expect(workspaces.connectWorkspace(wid('alpha'))).resolves.toBe('s-fresh-2')
  })

  it('a rejected first prompt keeps the blank session eligible for connectWorkspace reuse', async () => {
@@ -285,6 +291,84 @@ describe('WorkspacesService', () => {
    }))
    await expect(workspaces.delete(wid('ghost'))).rejects.toThrow(/workspace-not-found: gone/)
  })
+
+  it('archives a session, projects the set from the response, list, and frame, and clears only the current one', async () => {
+    const ctx = new Context()
+    const api = new FakeApiClient()
+    const sessions = new SessionsService(ctx, api)
+    const workspaces = new WorkspacesService(ctx, api, sessions)
+    api.onList = () => Promise.resolve(ok({
+      items: [
+        { sessionId: sid('s-open'), updatedAt: 2, running: false, blank: false },
+        { sessionId: sid('s-idle'), updatedAt: 1, running: false, blank: false },
+      ],
+    }) as never)
+    await sessions.refresh()
+    sessions.open(sid('s-open'))
+
+    // Archiving a non-current session installs the unary echo and keeps the selection.
+    await expect(workspaces.archiveSession(sid('s-idle'))).resolves.toBeUndefined()
+    expect(api.callsOf('workspace.archiveSession')).toEqual([{ sessionId: 's-idle' }])
+    expect(workspaces.list.getSnapshot().archivedSessionIds).toEqual(['s-idle'])
+    expect(sessions.list.getSnapshot().current).toBe('s-open')
+
+    // Archiving the current session clears it into the New Session view state.
+    api.onWorkspaceArchiveSession = () => Promise.resolve(ok({ archivedSessionIds: [sid('s-idle'), sid('s-open')] }))
+    await workspaces.archiveSession(sid('s-open'))
+    expect(workspaces.list.getSnapshot().archivedSessionIds).toEqual(['s-idle', 's-open'])
+    expect(sessions.list.getSnapshot().current).toBeUndefined()
+
+    // A Host failure leaves the set and the selection untouched.
+    api.onWorkspaceArchiveSession = () => Promise.resolve(err({
+      code: 'session-not-found', message: 'no session ghost', details: { sessionId: sid('ghost') },
+    }))
+    await expect(workspaces.archiveSession(sid('ghost'))).rejects.toThrow(/session-not-found/)
+    expect(workspaces.list.getSnapshot().archivedSessionIds).toEqual(['s-idle', 's-open'])
+
+    // The changed frame and the list baseline both re-install the full set.
+    workspaces.handleHostEnvelope({
+      rpcId: 'frame' as never,
+      payload: { type: 'host/archived-sessions-changed', archivedSessionIds: [sid('s-idle')] },
+    } as never)
+    // Frame installs ride the notifier's microtask batch before projecting.
+    await new Promise(resolve => setTimeout(resolve, 0))
+    expect(workspaces.list.getSnapshot().archivedSessionIds).toEqual(['s-idle'])
+    api.onWorkspaceList = () => Promise.resolve(ok({ items: [], archivedSessionIds: [sid('s-open')] }) as never)
+    await workspaces.refresh()
+    expect(workspaces.list.getSnapshot().archivedSessionIds).toEqual(['s-open'])
+  })
+
+  it('clears a current archived by a remote frame and shields the set from a stale in-flight baseline', async () => {
+    const ctx = new Context()
+    const api = new FakeApiClient()
+    const sessions = new SessionsService(ctx, api)
+    const workspaces = new WorkspacesService(ctx, api, sessions)
+    api.onList = () => Promise.resolve(ok({
+      items: [{ sessionId: sid('s-open'), updatedAt: 1, running: false, blank: false }],
+    }) as never)
+    await sessions.refresh()
+    sessions.open(sid('s-open'))
+
+    // A stale baseline is in flight (older, empty set) when another tab's
+    // archive frame lands: the frame clears the current selection and its
+    // set survives the baseline's later resolution.
+    const gate = deferred<Awaited<ReturnType<FakeApiClient['onWorkspaceList']>>>()
+    api.onWorkspaceList = () => gate.promise
+    const hydration = workspaces.refresh()
+    workspaces.handleHostEnvelope({
+      rpcId: 'frame' as never,
+      payload: { type: 'host/archived-sessions-changed', archivedSessionIds: [sid('s-open')] },
+    } as never)
+    await new Promise(resolve => setTimeout(resolve, 0))
+    expect(sessions.list.getSnapshot().current).toBeUndefined()
+    gate.resolve(ok({ items: [], archivedSessionIds: [] }))
+    await hydration
+    expect(workspaces.list.getSnapshot().archivedSessionIds).toEqual(['s-open'])
+    // The next (fresh) baseline is authoritative again.
+    api.onWorkspaceList = () => Promise.resolve(ok({ items: [], archivedSessionIds: [] }) as never)
+    await workspaces.refresh()
+    expect(workspaces.list.getSnapshot().archivedSessionIds).toEqual([])
+  })
 })

 describe('startInitialSelection', () => {
--- a/packages/client/test-runtime/src/fixtures.ts
+++ b/packages/client/test-runtime/src/fixtures.ts
@@ -73,6 +73,7 @@ export function conversationSnapshot(sessionId: SessionId): ConversationSnapshot
 export function workspaceListState(): WorkspaceListState {
  return {
    items: [],
+    archivedSessionIds: [],
    state: 'idle',
    phase: 'ready',
    error: null,
--- a/packages/client/test-runtime/src/workspaces.ts
+++ b/packages/client/test-runtime/src/workspaces.ts
@@ -186,4 +186,21 @@ export class TestWorkspaces implements IWorkspaces {
    if (stub !== undefined) return await (stub(workspaceId, sessionId, beforeSessionId) as Promise<WorkspaceView>)
    return { workspaceId, title: '', path: '', sessionIds: [sessionId] } as unknown as WorkspaceView
  }
+
+  /**
+   * Archive a session (recorded). The default mirrors the production face's
+   * observable effect: the id joins the list state's archive set.
+   * @param sessionId - session to archive.
+   */
+  async archiveSession(sessionId: SessionId): Promise<void> {
+    this.calls.push({ method: 'archiveSession', args: [sessionId] })
+    const stub = this.stubs.get('archiveSession')
+    if (stub !== undefined) {
+      await (stub(sessionId) as Promise<void>)
+      return
+    }
+    await this.update((draft) => {
+      draft.archivedSessionIds = [...draft.archivedSessionIds, sessionId]
+    })
+  }
 }
--- a/packages/client/test-runtime/tests/runtime.spec.tsx
+++ b/packages/client/test-runtime/tests/runtime.spec.tsx
@@ -551,8 +551,12 @@ describe('workspaces action face', () => {
    await ws.openPath('/proj/file.ts')
    const moved = await ws.insertSessionBefore('w1' as WorkspaceId, 's1' as SessionId, 's2' as SessionId)
    expect(moved.sessionIds).toEqual(['s1'])
+    // Default archive mirrors the production effect: the id joins the list
+    // state's archive set (features render against the same snapshot).
+    await ws.archiveSession('s1' as SessionId)
+    expect(ws.list.getSnapshot().archivedSessionIds).toEqual(['s1'])
    expect(ws.calls.map(c => c.method)).toEqual(
-      ['create', 'create', 'pickDirectory', 'rename', 'delete', 'openPath', 'insertSessionBefore'])
+      ['create', 'create', 'pickDirectory', 'rename', 'delete', 'openPath', 'insertSessionBefore', 'archiveSession'])

    ws.stub('create', () => Promise.resolve({ workspaceId: 'ws-x', title: 'X', path: '/x', sessionIds: [] } as never))
    ws.stub('pickDirectory', () => Promise.resolve('/picked'))
@@ -560,12 +564,16 @@ describe('workspaces action face', () => {
    ws.stub('delete', () => Promise.resolve())
    ws.stub('openPath', () => Promise.resolve())
    ws.stub('insertSessionBefore', () => Promise.resolve({ workspaceId: 'w1', title: '', path: '', sessionIds: [] } as never))
+    ws.stub('archiveSession', () => Promise.resolve())
    expect((await ws.create({ name: 'y' })).title).toBe('X')
    await expect(ws.pickDirectory()).resolves.toBe('/picked')
    expect((await ws.rename('w1' as WorkspaceId, 'z')).title).toBe('S')
    await ws.delete('w1' as WorkspaceId)
    await ws.openPath('/other')
    expect((await ws.insertSessionBefore('w1' as WorkspaceId, 's1' as SessionId)).sessionIds).toEqual([])
+    // The stub replaces the default set mutation: the set stays as-is.
+    await ws.archiveSession('s2' as SessionId)
+    expect(ws.list.getSnapshot().archivedSessionIds).toEqual(['s1'])
    await runtime.dispose()
  })
 })
--- a/packages/client/ui-conversation/README.i18n.yaml
+++ b/packages/client/ui-conversation/README.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/client/ui-conversation/README.md
-README.md: 7c6e36409efd5f2f9224e85a9cbd3a5e515833c1
-README.zh.md: 7661826153bc44ff47a660fa49a4ffd902d93bdd
+README.md: b183aab56a10c3a22eeab31f8b1b0e6b5219beba
+README.zh.md: af6427774a048de324d57bc9856f77547e9a03cc
--- a/packages/client/ui-conversation/README.md
+++ b/packages/client/ui-conversation/README.md
@@ -2,7 +2,7 @@

 English | [中文](README.zh.md)

-Conversation domain: skeleton (header/tabs/composer/empty state), chat view (grouped step-summary flow, streaming tail isolation, per-tool row slot with a bash sample registrant and the todo row), composer dock (session stats sticky with the input), input dock (queue rows plus the todo plan strip), minimal details panel, scope-addressed ConversationService. Contract: api-contracts v3 §7 plus the slot terminal design (store seat / props shares).
+Conversation domain: skeleton (header/tabs/composer/empty state), chat view (grouped step-summary flow, streaming tail isolation, an animated left-to-right gradient `Deep diving...` turn status, per-tool row slot with a bash sample registrant and the todo row), composer dock (session stats sticky with the input), input dock (hairline-separated queue rows plus the todo plan strip), minimal details panel, scope-addressed ConversationService. Contract: api-contracts v3 §7 plus the slot terminal design (store seat / props shares).

 The resident conversation shell survives no-session and session transitions. Without a current session it renders a disabled input bar; its root-scoped `conversation.hero.workspace` slot hosts the Workspace picker. Selecting a Workspace connects or reuses its Host-owned blank session and opens that session without replacing the shell. Blank sessions render the same composer body as active sessions, while the InputHub carries drafts across Workspace switches and mirrors them into the session store. In the active phase the session header occupies the top as ordinary column chrome; beneath it a scrollport (`data-conversation-scroll`) holds the flowing views and the sticky composer stack (stats dock + input docks + bar). Wheel over the textarea chains: the capped draft scrolls locally until its edge, then forwards to that host.

--- a/packages/client/ui-conversation/README.zh.md
+++ b/packages/client/ui-conversation/README.zh.md
@@ -2,7 +2,7 @@

 [English](README.md) | 中文

-会话领域：骨架（标题栏／标签页／编辑器／空状态）、聊天视图（分组步骤摘要流、流式尾部隔离、逐工具行 slot 及一个 bash 示例注册方与 todo 行）、编辑器 dock（与输入区一同 sticky 的会话统计行）、输入区 dock（队列行加 todo 计划条）、最小详情面板、按 scope 寻址的 ConversationService。契约：api-contracts v3 §7 加 slot 终端设计（store seat／props share）。
+会话领域：骨架（标题栏／标签页／编辑器／空状态）、聊天视图（分组步骤摘要流、流式尾部隔离、带从左到右动态渐变的 `Deep diving...` 轮次状态、逐工具行 slot 及一个 bash 示例注册方与 todo 行）、编辑器 dock（与输入区一同 sticky 的会话统计行）、输入区 dock（带发丝分界线的队列行加 todo 计划条）、最小详情面板、按 scope 寻址的 ConversationService。契约：api-contracts v3 §7 加 slot 终端设计（store seat／props share）。

 常驻会话壳会跨无会话与会话状态切换而保留。没有当前会话时，它会渲染禁用输入栏；其根作用域的 `conversation.hero.workspace` slot 承载 Workspace 选择器。选择 Workspace 会连接或复用由 Host 拥有的空白会话，并在不替换会话壳的情况下打开该会话。空白会话与活跃会话渲染相同的输入区主体；InputHub 则在 Workspace 切换间携带草稿，并将草稿镜像到会话 store。活跃阶段会话标题栏以普通列 chrome 占据顶部；其下滚动容器（`data-conversation-scroll`）承载流动排版的各视图与 sticky 编辑器栈（统计 dock＋输入区 dock＋输入栏）。textarea 上的滚轮会链式处理：限高草稿先在本地滚动，到达边缘后再转交给该宿主。

--- a/packages/client/ui-conversation/src/client/chat/ChatView.module.css
+++ b/packages/client/ui-conversation/src/client/chat/ChatView.module.css
@@ -66,33 +66,45 @@
  border-left: 1px solid var(--dsw-alias-border-l2);
 }

-/* Turn loader: one row of four 2.5px pixels (StateDot blue) chasing left to
-   right with a stepped trail — flat keyframe holds, no tweening. Phase
-   offsets come from per-rect animation-delay (index * -250ms) set inline
-   by the component. */
-.turnDots {
+/* Turn activity keeps the former loader's one-line footprint. A pale
+   brand-blue band sweeps from left to right; reduced-motion keeps it static. */
+.turnStatus {
  align-self: flex-start;
  flex: none;
-  display: flex;
+  display: inline-flex;
  align-items: center;
-  /* One message line box: the dots center inside the text line height. */
  height: 26px;
-  /* Same pin as StateDot: ongoing blue has no alias token (business-primary
-     is the 500 step, not this 450). */
-  color: var(--dsw-static-deepseek-450);
+  font: var(--dsw-font-s-strong-14);
+  white-space: nowrap;
+  background: linear-gradient(
+    90deg,
+    var(--dsw-static-deepseek-500) 0%,
+    var(--dsw-static-deepseek-500) 40%,
+    var(--dsw-static-deepseek-200) 50%,
+    var(--dsw-static-deepseek-500) 60%,
+    var(--dsw-static-deepseek-500) 100%
+  );
+  background-position: 100% 0;
+  background-size: 250% 100%;
+  background-clip: text;
+  color: transparent;
+  -webkit-background-clip: text;
+  -webkit-text-fill-color: transparent;
+  animation: dsh-turn-status-shimmer 1.8s linear infinite;
 }

-.turnDotCell {
-  fill: currentColor;
-  opacity: 0.15;
-  animation: dsh-turn-dots-chase 1s infinite;
+@keyframes dsh-turn-status-shimmer {
+  to {
+    background-position: 0 0;
+  }
 }

-@keyframes dsh-turn-dots-chase {
-  0%, 24.9% { opacity: 1; }
-  25%, 49.9% { opacity: 0.6; }
-  50%, 74.9% { opacity: 0.35; }
-  75%, 100% { opacity: 0.15; }
+@media (prefers-reduced-motion: reduce) {
+  .turnStatus {
+    background-position: 0 0;
+    background-size: 100% 100%;
+    animation: none;
+  }
 }

 .hint {
--- a/packages/client/ui-conversation/src/client/chat/ChatView.tsx
+++ b/packages/client/ui-conversation/src/client/chat/ChatView.tsx
@@ -204,36 +204,11 @@ const CommandRow = memo(function CommandRow({ renderSlot, node, t }: {
  )
 })

-/** Turn loader: one row of four 2.5px pixels (half a notch above the StateDot
- *  2px cell, same blue) chasing left to right with a stepped trail — flat
- *  keyframe holds, no tweening, no rotation. Phase offsets come from
- *  per-rect animation-delay. */
-const LOADER_CELLS = [0, 5, 10, 15] as const
-
-function TurnDots() {
+/** Turn-level model activity label retained across first-token, tool, and streaming phases. */
+function TurnStatus() {
  return (
-    /* The wrapper is a 26px line box (message line height) so the loader
-       occupies one text line and centers the dots inside it. */
-    <div className={css.turnDots} aria-hidden="true">
-      <svg
-        width="17.5"
-        height="2.5"
-        viewBox="0 0 17.5 2.5"
-        shapeRendering="crispEdges"
-      >
-        {LOADER_CELLS.map((x, index) => (
-          <rect
-            key={x}
-            className={css.turnDotCell}
-            x={x}
-            y="0"
-            width="2.5"
-            height="2.5"
-            /* Negative delay phases the chase so every cell animates from mount. */
-            style={{ animationDelay: `${(index - LOADER_CELLS.length) * 250}ms` }}
-          />
-        ))}
-      </svg>
+    <div className={css.turnStatus} role="status" aria-live="polite">
+      Deep diving...
    </div>
  )
 }
@@ -491,7 +466,7 @@ export function ChatView({
              double-render the same wait. */}
          {/* Turn-level loading signal: rides the whole running turn (first-token
              wait, tool execution, streaming) so it never flickers per step. */}
-          {running && <TurnDots />}
+          {running && <TurnStatus />}
        </div>
        {!atBottom && (
          <div className={css.toBottomSlot}>
--- a/packages/client/ui-conversation/src/client/queue/QueueDock.module.css
+++ b/packages/client/ui-conversation/src/client/queue/QueueDock.module.css
@@ -107,6 +107,10 @@
  border-radius: 8px;
 }

+.row + .row {
+  box-shadow: inset 0 1px 0 var(--dsw-alias-border-l1);
+}
+
 .preview,
 .editor {
  flex: 1 1 auto;
--- a/packages/client/ui-conversation/tests/chat-code-subcalls.spec.tsx
+++ b/packages/client/ui-conversation/tests/chat-code-subcalls.spec.tsx
@@ -128,7 +128,7 @@ async function bench(snapshot: ConversationSnapshot) {
  ctx.provide('sessions', sessionsFake)
  const workspaces = {
    list: createSnapshotStore<WorkspaceListState>({
-      items: [], state: 'idle', phase: 'ready', error: null,
+      items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
      baselinesReady: true, recentWorkspaceId: undefined,
    }),
    startSession: vi.fn(),
--- a/packages/client/ui-conversation/tests/chat-view.spec.tsx
+++ b/packages/client/ui-conversation/tests/chat-view.spec.tsx
@@ -5,7 +5,7 @@

 import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
 import { Profiler } from 'react'
-import { act, cleanup, fireEvent, render } from '@testing-library/react'
+import { act, cleanup, fireEvent, render, within } from '@testing-library/react'
 import type {
  AssistantMessageNode, CommandNode, ConversationNode, ConversationSnapshot,
  ModelRetryNode, RunningToolCall, SessionId, SessionListState, ToolResultNode,
@@ -94,7 +94,7 @@ function emptySessions() {

 function emptyWorkspaces() {
  const store = createSnapshotStore<WorkspaceListState>({
-    items: [], state: 'idle', phase: 'ready', error: null,
+    items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
    baselinesReady: true, recentWorkspaceId: undefined,
  })
  return bindSnapshotSelector(store)
@@ -254,16 +254,16 @@ describe('ChatView', () => {
    } as const satisfies ConversationNode
    const h = makeHarness({ nodes: [user(1, 'try'), retryNode], running: true })
    const view = render(<h.ChatView {...h.props} />)
-    const disclosure = view.container.querySelector('details')
-    expect(disclosure?.dataset.active).toBe('true')
-    expect(view.getByRole('status').textContent).toBe('正在重试模型请求（1/2） · 1s')
+    const disclosure = view.container.querySelector('details') as HTMLDetailsElement
+    expect(disclosure.dataset.active).toBe('true')
+    expect(within(disclosure).getByRole('status').textContent).toBe('正在重试模型请求（1/2） · 1s')

    act(() => {
      h.set({ nodes: [user(1, 'try'), retryNode, nextRetry] })
    })
-    expect(view.getAllByRole('status')).toHaveLength(1)
+    expect(within(disclosure).getAllByRole('status')).toHaveLength(1)
    expect(view.container.querySelector('details')).toBe(disclosure)
-    expect(view.getByRole('status').textContent).toBe('正在重试模型请求（2/2） · 1s')
+    expect(within(disclosure).getByRole('status').textContent).toBe('正在重试模型请求（2/2） · 1s')

    act(() => {
      h.set({
@@ -277,14 +277,15 @@ describe('ChatView', () => {
        running: false,
      })
    })
-    expect(disclosure?.dataset.active).toBeUndefined()
-    expect(view.getByRole('status').textContent).toBe('已重试模型请求（2/2） · 1s')
+    expect(disclosure.dataset.active).toBeUndefined()
+    expect(within(disclosure).getByRole('status').textContent).toBe('已重试模型请求（2/2） · 1s')

    act(() => {
      h.set({ nodes: [user(1, 'try'), { ...retry(6), retryState: 'cancelled' }], running: true })
    })
-    expect(disclosure?.dataset.active).toBeUndefined()
-    expect(view.getByRole('status').textContent).toContain('重试已取消')
+    const cancelledDisclosure = view.container.querySelector('details') as HTMLDetailsElement
+    expect(cancelledDisclosure.dataset.active).toBeUndefined()
+    expect(within(cancelledDisclosure).getByRole('status').textContent).toContain('重试已取消')
  })

  it('the expanded row Inspect pill hands the call id to inspectCall', () => {
@@ -448,6 +449,7 @@ describe('ChatView', () => {
    const view = render(<h.ChatView {...h.props} />)
    expect(view.container.querySelector('[data-state="running"]')).not.toBeNull()
    expect(view.getByText('cmd-r1')).toBeTruthy()
+    expect(view.getByRole('status').textContent).toBe('Deep diving...')
  })

  it('dispatches each tool row through the keyed slot with the tool name as entryKey', () => {
--- a/packages/client/ui-conversation/tests/diff-card.spec.tsx
+++ b/packages/client/ui-conversation/tests/diff-card.spec.tsx
@@ -287,7 +287,7 @@ describe('DetailsPanel diff Output section', () => {
        phase: 'ready',
      })
    const workspaces = createSnapshotStore<WorkspaceListState>({
-      items: [], state: 'idle', phase: 'ready', error: null,
+      items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
      baselinesReady: true, recentWorkspaceId: undefined,
    })
    return render(
--- a/packages/client/ui-conversation/tests/gate-branch-tails.spec.tsx
+++ b/packages/client/ui-conversation/tests/gate-branch-tails.spec.tsx
@@ -74,7 +74,7 @@ describe('render branch tails', () => {
    const emptyList = createSnapshotStore<SessionListState>(
      { ids: [], byId: {}, current: undefined, phase: 'ready' })
    const emptyWorkspaces = createSnapshotStore<WorkspaceListState>({
-      items: [], state: 'idle', phase: 'ready', error: null,
+      items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
      baselinesReady: true, recentWorkspaceId: undefined,
    })
    const view = render(
@@ -111,7 +111,7 @@ describe('render branch tails', () => {
    const emptyList = createSnapshotStore<SessionListState>(
      { ids: [], byId: {}, current: undefined, phase: 'ready' })
    const emptyWorkspaces = createSnapshotStore<WorkspaceListState>({
-      items: [], state: 'idle', phase: 'ready', error: null,
+      items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
      baselinesReady: true, recentWorkspaceId: undefined,
    })
    const view = render(
--- a/packages/client/ui-conversation/tests/input-bar.spec.tsx
+++ b/packages/client/ui-conversation/tests/input-bar.spec.tsx
@@ -96,7 +96,7 @@ function bench(over?: BenchOptions) {
      ids: [], byId: {}, current: undefined, phase: 'ready',
    })),
    useWorkspaces: bindSnapshotSelector(createSnapshotStore({
-      items: [], state: 'idle', phase: 'ready', error: null,
+      items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
      baselinesReady: true, recentWorkspaceId: undefined,
    })),
    useProjection: ((key: string, selector?: (v: unknown) => unknown) =>
--- a/packages/client/ui-conversation/tests/input-matrix.spec.tsx
+++ b/packages/client/ui-conversation/tests/input-matrix.spec.tsx
@@ -39,7 +39,7 @@ function mountBar(shell: SessionInputShell, over?: { running?: boolean; disabled
      ids: [], byId: {}, current: undefined, phase: 'ready',
    })),
    useWorkspaces: bindSnapshotSelector(createSnapshotStore({
-      items: [], state: 'idle', phase: 'ready', error: null,
+      items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
      baselinesReady: true, recentWorkspaceId: undefined,
    })),
    useProjection: (() => undefined),
--- a/packages/client/ui-conversation/tests/input-scenarios.spec.tsx
+++ b/packages/client/ui-conversation/tests/input-scenarios.spec.tsx
@@ -125,7 +125,7 @@ async function scopedBench(register?: (slash: SlashService) => void) {
      ids: [], byId: {}, current: undefined, phase: 'ready',
    })),
    useWorkspaces: bindSnapshotSelector(createSnapshotStore({
-      items: [], state: 'idle', phase: 'ready', error: null,
+      items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
      baselinesReady: true, recentWorkspaceId: undefined,
    })),
    useProjection: (() => undefined),
--- a/packages/client/ui-conversation/tests/skeleton.spec.tsx
+++ b/packages/client/ui-conversation/tests/skeleton.spec.tsx
@@ -62,7 +62,7 @@ function workspace(id = 'w1'): WorkspaceView {
 }

 const workspaceState = (items: readonly WorkspaceView[]): WorkspaceListState => ({
-  items, state: 'idle', phase: 'ready', error: null,
+  items, archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
  baselinesReady: true, recentWorkspaceId: undefined,
 })

--- a/packages/client/ui-conversation/tests/terminal-card.spec.tsx
+++ b/packages/client/ui-conversation/tests/terminal-card.spec.tsx
@@ -429,7 +429,7 @@ describe('DetailsPanel Output section', () => {
        phase: 'ready',
      })
    const workspaces = createSnapshotStore<WorkspaceListState>({
-      items: [], state: 'idle', phase: 'ready', error: null,
+      items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
      baselinesReady: true, recentWorkspaceId: undefined,
    })
    return render(
@@ -607,7 +607,7 @@ describe('DetailsPanel Output section', () => {
        useSessions={bindSnapshotSelector(createSnapshotStore<SessionListState>(
          { ids: [], byId: {}, current: undefined, phase: 'ready' }))}
        useWorkspaces={bindSnapshotSelector(createSnapshotStore<WorkspaceListState>({
-          items: [], state: 'idle', phase: 'ready', error: null,
+          items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
          baselinesReady: true, recentWorkspaceId: undefined,
        }))}
        useInput={(() => { throw new Error('unused') })}
--- a/packages/client/ui-conversation/tests/web-card.spec.tsx
+++ b/packages/client/ui-conversation/tests/web-card.spec.tsx
@@ -190,7 +190,7 @@ describe('DetailsPanel web Output section', () => {
    if (selection !== null) chat.actions.select(selection)
    const sessions = createSnapshotStore<SessionListState>({ ids: [], byId: {}, current: undefined, phase: 'ready' })
    const workspaces = createSnapshotStore<WorkspaceListState>({
-      items: [], state: 'idle', phase: 'ready', error: null,
+      items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
      baselinesReady: true, recentWorkspaceId: undefined,
    })
    return render(
--- a/packages/client/ui-layout/tests/app-frame.spec.tsx
+++ b/packages/client/ui-layout/tests/app-frame.spec.tsx
@@ -77,7 +77,7 @@ function mountFrame() {
    return sel(sessionState)
  }) as never
  const workspaceState: WorkspaceListState = {
-    items: [], state: 'idle', phase: 'ready', error: null,
+    items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
    baselinesReady: baselinesReady.current, recentWorkspaceId: undefined,
  }
  const element = () => (
--- a/packages/client/ui-theme/tests/appearance-row.spec.tsx
+++ b/packages/client/ui-theme/tests/appearance-row.spec.tsx
@@ -27,7 +27,7 @@ function emptySessions() {
 }
 function emptyWorkspaces() {
  const store = createSnapshotStore<WorkspaceListState>({
-    items: [], state: 'idle', phase: 'ready', error: null,
+    items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null,
    baselinesReady: true, recentWorkspaceId: undefined,
  })
  return bindSnapshotSelector(store)
--- a/packages/client/ui-trajectory/tests/views.spec.tsx
+++ b/packages/client/ui-trajectory/tests/views.spec.tsx
@@ -113,7 +113,7 @@ function emptySessions() {

 function emptyWorkspaces() {
  const store = createSnapshotStore<WorkspaceListState>({
-    items: [], state: 'idle', phase: 'ready', error: null, baselinesReady: true,
+    items: [], archivedSessionIds: [], state: 'idle', phase: 'ready', error: null, baselinesReady: true,
    recentWorkspaceId: undefined,
  })
  return bindSnapshotSelector(store)
--- a/packages/client/ui-workspace/README.i18n.yaml
+++ b/packages/client/ui-workspace/README.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/client/ui-workspace/README.md
-README.md: f71bfa09c795bd69e1f49c8f6dffffd5959dbe47
-README.zh.md: 80b53d85eb210b0e7a7ace1699d6bbfc9a836606
+README.md: cc73214a281c6950acf8846f0bae3214c8726934
+README.zh.md: c0b6472c7db74dbfd4b0afd19a258e0132a7c534
--- a/packages/client/ui-workspace/README.md
+++ b/packages/client/ui-workspace/README.md
@@ -6,7 +6,7 @@ Shared Workspace browser and picker plugin. `WorkspaceBrowser` fills the sidebar

 The browser renders grouped or flat Session rows from the global runtime hooks and owns the Workspace create/rename and in-Workspace reorder flows. A non-blank search query replaces either browsing mode with one flat result list: case-insensitive title and Workspace substring matches appear immediately, while a 250 ms debounced Host request adds ranked current-conversation content matches and snippets. The English search input and its defensive request path remove NUL, cap the query at the wire schema's 500 UTF-16 code units without splitting a surrogate pair, and preserve the existing debounce and cancellation behavior. Each new query aborts the preceding request; a failed content search leaves metadata matches visible with a warning. The list is capped at 20, asks the user to narrow broader queries, and opens the selected Session without clearing the query or jumping to a specific event.

-The picker lists real Host Workspace entities through the global `useWorkspaces` hook. Selecting a Workspace invokes the slot owner's `onPick` callback to retarget the frontend Session object. Each registration declares a **directory-flow child hole** (`single` kind: `conversation.hero.workspace.directoryFlow` / `sidebar.workspaces.directoryFlow`) that the composed picker package's client half fills with its picking interaction — the [`-native`](../../host/directory-picker-native/README.md) backend's renderless OS-chooser driver today, an in-app browsing dialog under a `-browse` composition. The flat **Open local folder...** action renders only while the surface's hole is occupied (occupancy read per menu render; an empty hole means the composition has no picking affordance — the seam's documented no-flow default). This package owns the trigger and the adoption: the occupant reports one picked path per open through the hole's owner conversation (`open`/`busy`/`onPicked`/`onCancel`/`onError`), and the owner adopts it through the object layer, selecting the committed Workspace only after its list projection has refreshed; cancellation is silent, and errors land in the retryable folder dialog whose **Choose again** reopens the flow. **Create a new workspace** retains the name dialog and disables names already present in that list, while the Host remains authoritative for concurrent or non-UI callers. The runtime Session and Workspace services own materialization. The Workspace row's Delete action opens a confirmation that states the retention boundary, blocks duplicate submission, and keeps failures open; success removes the group while its Sessions remain under Ungrouped. The Session row's Rename action opens the same browser-owned dialog pattern prefilled with the row's display title: no client-side conflict rule exists (the host normalizes and may reject with `title-invalid`, rendered in the dialog alert), and confirming an unchanged title is deliberately allowed — it pins the current automatic title against regeneration.
+The picker lists real Host Workspace entities through the global `useWorkspaces` hook. Selecting a Workspace invokes the slot owner's `onPick` callback to retarget the frontend Session object. Each registration declares a **directory-flow child hole** (`single` kind: `conversation.hero.workspace.directoryFlow` / `sidebar.workspaces.directoryFlow`) that the composed picker package's client half fills with its picking interaction — the [`-native`](../../host/directory-picker-native/README.md) backend's renderless OS-chooser driver today, an in-app browsing dialog under a `-browse` composition. The flat **Open local folder...** action renders only while the surface's hole is occupied (occupancy read per menu render; an empty hole means the composition has no picking affordance — the seam's documented no-flow default). This package owns the trigger and the adoption: the occupant reports one picked path per open through the hole's owner conversation (`open`/`busy`/`onPicked`/`onCancel`/`onError`), and the owner adopts it through the object layer, selecting the committed Workspace only after its list projection has refreshed; cancellation is silent, and errors land in the retryable folder dialog whose **Choose again** reopens the flow. **Create a new workspace** retains the name dialog and disables names already present in that list, while the Host remains authoritative for concurrent or non-UI callers. The runtime Session and Workspace services own materialization. The Workspace row's Delete action opens a confirmation that states the retention boundary, blocks duplicate submission, and keeps failures open; success removes the group while its Sessions remain under Ungrouped. The Session row's Rename action opens the same browser-owned dialog pattern prefilled with the row's display title: no client-side conflict rule exists (the host normalizes and may reject with `title-invalid`, rendered in the dialog alert), and confirming an unchanged title is deliberately allowed — it pins the current automatic title against regeneration. The Session row's Archive action commits without a confirmation dialog (non-destructive: the log and the workspace accounting slot remain) through `ctx.workspaces.archiveSession`; the row disappears from every grouping surface — workspace groups, Ungrouped, content search, and the flat list — when the archive-set echo lands, and failures are console diagnostics that leave the tree unchanged. A blank New Session row is a pure placeholder: it renders no row menu and no time label (nothing has happened in it yet), so rename, fork, and archive first apply once the first prompt lands.

 The Session row's Fork action forks at the source's last completed turn, increments the inherited persisted title on the client, and then opens the child; a trailing ASCII or fullwidth parenthesized number is incremented in the same style, while an unnumbered title gets ` (1)` appended. The source and child always appear as peer rows within a workspace group, with lineage retained only as session data. A fork or rename failure leaves the current selection unchanged; after a rename failure, the created child remains in the list.

@@ -23,5 +23,5 @@ None; this package neither assembles nor sends a provider request.
 ## Known Limitations and Deferred Work

 - **No fuzzy content search or event deep links** — the content backend uses literal token/phrase matching, and selecting a result opens the Session rather than the matching event.
- **No Session deletion control** — the Session menu's Delete row remains visual-only; Workspace registration deletion does not delete Sessions.
+- **No Session deletion or unarchive control** — archiving replaces the former Delete placeholder; archived sessions have no viewing or unarchive surface yet, and Workspace registration deletion does not delete Sessions.
 - **Native folder selection depends on the local Host carrier** — under the `-native` composition, fixture-only or remote browser deployments cannot open a local operating-system dialog; platform failures are shown in a retryable modal. Remote-capable picking is the `-browse` composition's in-app flow.
--- a/packages/client/ui-workspace/README.zh.md
+++ b/packages/client/ui-workspace/README.zh.md
@@ -6,7 +6,7 @@

 该浏览器通过全局运行时钩子将 Session 行渲染为分组或扁平形式，并负责 Workspace 创建／重命名和 Workspace 内的重排序流程。非空白查询会以单一扁平结果列表替代任一浏览模式：不区分大小写的标题和 Workspace 子串匹配项会立即显示，经 250 ms 防抖的 Host 请求则会加入经过排序的当前对话内容匹配项及其摘要片段。英文搜索输入框及其防御性请求路径会移除 NUL，将查询限制在传输 schema 规定的 500 个 UTF-16 code unit 内且不会拆分 surrogate pair，并保留现有的防抖与取消行为。每次新查询都会中止前一个请求；内容搜索失败时，元数据匹配项仍会显示，同时给出警告。列表最多显示 20 条结果，并会在查询过宽时提示用户缩小范围；打开所选 Session 时既不会清除查询，也不会跳转至特定事件。

-该选择器通过全局 `useWorkspaces` hook 列出真实的 Host Workspace 实体。选择 Workspace 会调用 slot owner 的 `onPick` 回调，重新定位前端 Session 对象。每个注册各自声明一个**目录流子洞**（`single` kind：`conversation.hero.workspace.directoryFlow`／`sidebar.workspaces.directoryFlow`），由组合的选择器包 client half 填入其选取交互——今天是 [`-native`](../../host/directory-picker-native/README.md) 后端的无渲染 OS 选择器驱动，`-browse` 组合下则是应用内浏览对话框。平铺显示的 **打开本地文件夹…** 操作仅在本表层的洞被占用时渲染（每次菜单渲染读取占用状态；洞为空意味着该组合没有选目录能力——seam 文档化的无流程默认行为）。本包持有触发与接纳：占用者经洞的 owner 会话（`open`/`busy`/`onPicked`/`onCancel`/`onError`）每次打开上报一个所选路径，owner 通过对象层接纳它，并等待 Workspace 列表投影刷新后才选中已提交的 Workspace；取消操作不会显示提示，错误落入可重试的文件夹对话框，其 **重新选择** 会重新打开流程。**创建新工作区** 操作保留名称对话框，并禁用列表中已有的名称，而 Host 对并发或非 UI 调用方仍具有最终决定权。运行时 Session 与 Workspace 服务负责物化。Workspace 行内的 Delete 操作会打开确认框，说明保留边界、阻止重复提交，并在失败时保持打开；成功后，该分组会被移除，其 Session 则留在 Ungrouped 下。Session 行内的 Rename 操作打开同款浏览器持有的对话框，并以该行的显示标题预填：客户端不设名称冲突规则（host 负责规范化，可能以 `title-invalid` 拒绝，错误渲染在对话框告警区）；确认未修改的标题是有意允许的——这正是把当前自动标题钉住、不再被重新生成覆盖的手势。
+该选择器通过全局 `useWorkspaces` hook 列出真实的 Host Workspace 实体。选择 Workspace 会调用 slot owner 的 `onPick` 回调，重新定位前端 Session 对象。每个注册各自声明一个**目录流子洞**（`single` kind：`conversation.hero.workspace.directoryFlow`／`sidebar.workspaces.directoryFlow`），由组合的选择器包 client half 填入其选取交互——今天是 [`-native`](../../host/directory-picker-native/README.md) 后端的无渲染 OS 选择器驱动，`-browse` 组合下则是应用内浏览对话框。平铺显示的 **打开本地文件夹…** 操作仅在本表层的洞被占用时渲染（每次菜单渲染读取占用状态；洞为空意味着该组合没有选目录能力——seam 文档化的无流程默认行为）。本包持有触发与接纳：占用者经洞的 owner 会话（`open`/`busy`/`onPicked`/`onCancel`/`onError`）每次打开上报一个所选路径，owner 通过对象层接纳它，并等待 Workspace 列表投影刷新后才选中已提交的 Workspace；取消操作不会显示提示，错误落入可重试的文件夹对话框，其 **重新选择** 会重新打开流程。**创建新工作区** 操作保留名称对话框，并禁用列表中已有的名称，而 Host 对并发或非 UI 调用方仍具有最终决定权。运行时 Session 与 Workspace 服务负责物化。Workspace 行内的 Delete 操作会打开确认框，说明保留边界、阻止重复提交，并在失败时保持打开；成功后，该分组会被移除，其 Session 则留在 Ungrouped 下。Session 行内的 Rename 操作打开同款浏览器持有的对话框，并以该行的显示标题预填：客户端不设名称冲突规则（host 负责规范化，可能以 `title-invalid` 拒绝，错误渲染在对话框告警区）；确认未修改的标题是有意允许的——这正是把当前自动标题钉住、不再被重新生成覆盖的手势。Session 行内的 Archive 操作不经确认对话框直接提交（非破坏性：日志和 workspace 记账席位保持不变），通过 `ctx.workspaces.archiveSession` 归档；归档集合回声落地后，该行从所有分组视图——workspace 分组、Ungrouped、内容搜索和平铺列表——中消失，失败只作为控制台诊断输出，树保持不变。blank「新会话」行是纯占位：不渲染行菜单和时间标签（其中还没有发生任何事），rename/fork/归档都从首条 prompt 落地后才可用。

 Session 行内的 Fork 操作在源会话最后一个已完成轮次处 fork，在 client 端递增继承的持久化标题后再打开子会话；尾部半角或全角括号编号会原样式递增，无编号标题追加 ` (1)`。源会话与子会话在 workspace 组内始终作为同级行展示，谱系只保留为 session 数据。Fork 或改名失败都不会改变当前选中项，改名失败时已创建的子会话仍会留在列表中。

@@ -23,5 +23,5 @@ Session 行内的 Fork 操作在源会话最后一个已完成轮次处 fork，
 ## 已知限制与暂缓事项

 - **没有模糊内容搜索或事件深链接**：内容后端采用字面 token／短语匹配，选择结果会打开 Session，而不是匹配的事件。
- **没有 Session 删除控件**：Session 菜单的 Delete 行仍仅提供视觉效果；删除 Workspace 注册记录不会删除 Session。
+- **没有 Session 删除与取消归档控件**：归档取代了原先的 Delete 占位；已归档会话尚无查看或取消归档入口；删除 Workspace 注册记录不会删除 Session。
 - **原生文件夹选择依赖本地 Host 载体**：在 `-native` 组合下，仅使用 fixture（测试前置数据）的部署或远程浏览器部署无法打开本地操作系统对话框；模态框会显示平台故障，并允许重试。可远程的选取是 `-browse` 组合的应用内流程。
--- a/packages/client/ui-workspace/src/client/WorkspaceBrowser.tsx
+++ b/packages/client/ui-workspace/src/client/WorkspaceBrowser.tsx
@@ -102,18 +102,22 @@ type SessionTreeProps = Pick<
  'useSessions' | 'startSession' | 'open' | 'forkSession' | 'insertSessionBefore' | 't'
 > & {
  workspaces: readonly WorkspaceView[]
+  /** Registry-global archive set (hidden rows). */
+  archivedSessionIds: readonly SessionNode['id'][]
  /** Open the browser-owned rename dialog for a real Workspace group. */
  onRenameRequest: (workspaceId: WorkspaceId, currentTitle: string) => void
  /** Open the browser-owned delete-confirmation dialog for a real Workspace group. */
  onDeleteRequest: (workspaceId: WorkspaceId, currentTitle: string) => void
  /** Open the browser-owned session rename dialog. */
  onSessionRename: (sessionId: SessionNode['id'], currentTitle: string) => void
+  /** Archive a session (row menu action; the row disappears on the state echo). */
+  onSessionArchive: (sessionId: SessionNode['id']) => void
 }

 /** The scrolling session tree; unmounting at collapse settle drops the sessions subscription and expansion state. */
 function SessionTree({
-  useSessions, startSession, open, forkSession, workspaces,
-  onRenameRequest, onDeleteRequest, onSessionRename, insertSessionBefore, t,
+  useSessions, startSession, open, forkSession, workspaces, archivedSessionIds,
+  onRenameRequest, onDeleteRequest, onSessionRename, onSessionArchive, insertSessionBefore, t,
 }: SessionTreeProps) {
  const list = useSessions(s => s)
  const current = list.current
@@ -129,8 +133,8 @@ function SessionTree({
    setExpandedProjects(l => (l.includes(currentGroup) ? l : [...l, currentGroup]))
  }, [current, currentGroup])
  const groups = useMemo(
-    () => deriveGroups(list, workspaces, { expandedProjects }),
-    [list, workspaces, expandedProjects],
+    () => deriveGroups(list, workspaces, archivedSessionIds, { expandedProjects }),
+    [list, workspaces, archivedSessionIds, expandedProjects],
  )
  const now = Date.now()

@@ -209,6 +213,7 @@ function SessionTree({
                  onOpen={open}
                  onRename={onSessionRename}
                  onFork={forkSession}
+                  onArchive={onSessionArchive}
                  drag={dragProps}
                  t={t}
                />
@@ -223,9 +228,11 @@ function SessionTree({
 }

 /** The flat "In one list" body: every session a top-level row, newest-first. */
-function FlatList({ useSessions, open, forkSession, onSessionRename, t }: Pick<SessionTreeProps, 'useSessions' | 'open' | 'forkSession' | 'onSessionRename' | 't'>) {
+function FlatList({ useSessions, open, forkSession, onSessionRename, onSessionArchive, archivedSessionIds, t }: Pick<
+  SessionTreeProps, 'useSessions' | 'open' | 'forkSession' | 'onSessionRename' | 'onSessionArchive' | 'archivedSessionIds' | 't'
+>) {
  const list = useSessions(s => s)
-  const rows = useMemo(() => deriveFlat(list), [list])
+  const rows = useMemo(() => deriveFlat(list, archivedSessionIds), [list, archivedSessionIds])
  const now = Date.now()
  return (
    <div className={clsx(css.treeBody, css.wide)}>
@@ -242,6 +249,7 @@ function FlatList({ useSessions, open, forkSession, onSessionRename, t }: Pick<S
            onOpen={open}
            onRename={onSessionRename}
            onFork={forkSession}
+            onArchive={onSessionArchive}
            t={t}
          />
        ))}
@@ -263,12 +271,14 @@ function SearchResults({
  useSessions,
  open,
  workspaces,
+  archivedSessionIds,
  query,
  remote,
  resultLimit,
  t,
 }: Pick<SessionTreeProps, 'useSessions' | 'open' | 't'> & {
  workspaces: readonly WorkspaceView[]
+  archivedSessionIds: readonly SessionNode['id'][]
  query: string
  remote: RemoteSearchState
  resultLimit: number
@@ -278,8 +288,8 @@ function SearchResults({
    ? remote
    : { query, status: 'loading' as const, items: [], hasMore: false }
  const results = useMemo(
-    () => deriveSearchResults(list, workspaces, query, currentRemote, resultLimit),
-    [list, workspaces, query, currentRemote, resultLimit],
+    () => deriveSearchResults(list, workspaces, query, archivedSessionIds, currentRemote, resultLimit),
+    [list, workspaces, query, archivedSessionIds, currentRemote, resultLimit],
  )
  const pending = currentRemote.status === 'loading'
  const failed = currentRemote.status === 'error'
@@ -337,6 +347,7 @@ export function WorkspaceBrowser({
  forkSession,
  renameWorkspace,
  deleteWorkspace,
+  archiveSession,
  insertSessionBefore,
  createWorkspace,
  searchSessions,
@@ -346,6 +357,7 @@ export function WorkspaceBrowser({
  t,
 }: WorkspaceBrowserProps) {
  const workspaces = useWorkspaces(state => state.items)
+  const archivedSessionIds = useWorkspaces(state => state.archivedSessionIds)
  const groupBy = useStore(s => s.groupBy)
  // The query outlives the tree and the input (both wide-only) so collapsing
  // does not silently drop an in-progress filter.
@@ -475,6 +487,16 @@ export function WorkspaceBrowser({
    setSessionRenameError(null)
  }

+  // Archive is dialog-free: not destructive (the log and the accounting slot
+  // remain), so the menu action commits directly; the row disappears when the
+  // archive-set echo lands. Failures are non-fatal console diagnostics, the
+  // same posture as reorder rejections.
+  const onSessionArchive = (sessionId: SessionNode['id']) => {
+    archiveSession(sessionId).catch((reason: unknown) => {
+      console.warn('session archive rejected:', reason)
+    })
+  }
+
  // Delete dialog is separate from the row so a successful removal can
  // unmount that row without tearing down the in-flight confirmation state.
  const [deleteTarget, setDeleteTarget] = useState<{ workspaceId: WorkspaceId; title: string } | null>(null)
@@ -597,6 +619,7 @@ export function WorkspaceBrowser({
              useSessions={useSessions}
              open={open}
              workspaces={workspaces}
+              archivedSessionIds={archivedSessionIds}
              query={normalizedQuery}
              remote={remoteSearch}
              resultLimit={searchResultLimit}
@@ -607,15 +630,18 @@ export function WorkspaceBrowser({
            ? (
              <FlatList
                useSessions={useSessions} open={open} forkSession={forkSession}
-                onSessionRename={onSessionRename} t={t}
+                onSessionRename={onSessionRename} onSessionArchive={onSessionArchive}
+                archivedSessionIds={archivedSessionIds} t={t}
              />
            )
            : (
              <SessionTree
                useSessions={useSessions}
                onSessionRename={onSessionRename}
+                onSessionArchive={onSessionArchive}
                forkSession={forkSession}
                workspaces={workspaces}
+                archivedSessionIds={archivedSessionIds}
                startSession={startSession}
                open={open}
                insertSessionBefore={insertSessionBefore}
--- a/packages/client/ui-workspace/src/client/contract/slots.ts
+++ b/packages/client/ui-workspace/src/client/contract/slots.ts
@@ -113,6 +113,12 @@ export type WorkspaceBrowserInjected = DirectoryPickingInjected & {
  renameWorkspace: (workspaceId: WorkspaceId, title: string) => Promise<void>
  /** Delete only a Host Workspace registration; directory and Session logs remain. */
  deleteWorkspace: (workspaceId: WorkspaceId) => Promise<void>
+  /**
+   * Archive a Session into the registry-global set: hidden from grouping
+   * surfaces, log and accounting slot retained. Archiving the current
+   * session clears the selection into the New Session view state.
+   */
+  archiveSession: (sessionId: SessionId) => Promise<void>
  /**
   * Reorder a session inside its Workspace account (DOM-insertBefore
   * semantics: omitted anchor appends to the end). The view refreshes from
--- a/packages/client/ui-workspace/src/client/index.ts
+++ b/packages/client/ui-workspace/src/client/index.ts
@@ -92,6 +92,7 @@ export function apply(ctx: ClientContext): void {
    },
    renameWorkspace: async (workspaceId, title) => { await ctx.workspaces.rename(workspaceId, title) },
    deleteWorkspace: async (workspaceId) => { await ctx.workspaces.delete(workspaceId) },
+    archiveSession: async (sessionId) => { await ctx.workspaces.archiveSession(sessionId) },
    insertSessionBefore: async (workspaceId, sessionId, beforeSessionId) => {
      await ctx.workspaces.insertSessionBefore(workspaceId, sessionId, beforeSessionId)
    },
--- a/packages/client/ui-workspace/src/client/locales.ts
+++ b/packages/client/ui-workspace/src/client/locales.ts
@@ -45,7 +45,7 @@ export const zh = {
  'delete.desc': '将把“{name}”从工作区列表中移除。文件夹与会话记录会保留，其会话将显示在“未分组”下。',
  'delete.pending': '正在删除工作区…',
  'menu.fork': '分叉会话',
-  'menu.deleteSession': '删除会话',
+  'menu.archiveSession': '归档会话',
  'sessions.count.one': '{n} 个会话',
  'sessions.count.other': '{n} 个会话',
  'actions.workspace.aria': '工作区“{name}”的操作',
@@ -108,7 +108,7 @@ export const en = {
  'delete.desc': 'This removes “{name}” from the workspace list. The folder and session logs will be kept. Its sessions will appear under Ungrouped.',
  'delete.pending': 'Deleting workspace…',
  'menu.fork': 'Fork session',
-  'menu.deleteSession': 'Delete session',
+  'menu.archiveSession': 'Archive session',
  'sessions.count.one': '{n} session',
  'sessions.count.other': '{n} sessions',
  'actions.workspace.aria': 'Workspace actions for {name}',
--- a/packages/client/ui-workspace/src/client/rows/Rows.tsx
+++ b/packages/client/ui-workspace/src/client/rows/Rows.tsx
@@ -2,14 +2,14 @@
 * Workspace browser tree row components (figma Cell set 14:3080): pure presentational —
 * all data and callbacks arrive via props. Hover swaps (folder->chevron,
 * time->ellipsis, action buttons) are CSS-only. Row ... menus are visual-only
- * except workspace Rename/Delete and session Rename/Fork; the session and
- * workspace hover cards are suppressed while a menu is open.
+ * except workspace Rename/Delete and session Rename/Fork/Archive; the session
+ * and workspace hover cards are suppressed while a menu is open.
 */
 import { useState } from 'react'
 import clsx from 'clsx'
 import {
-  HoverCard, IconBranchOutline16, IconEditOutline16, IconEllipsisOutline16,
-  IconFolderClose16, IconFolderOpen16, IconPlusOutline16,
+  HoverCard, IconBranchOutline16, IconDownloadOutline16, IconEditOutline16,
+  IconEllipsisOutline16, IconFolderClose16, IconFolderOpen16, IconPlusOutline16,
  IconTrashOutline16, IconTriangleRightFill14, Menu, StateDot,
 } from '@deepseek-ai/dsh-client-ui-primitives'
 import type { WorkspaceBrowserProps } from '../contract/slots.ts'
@@ -175,7 +175,9 @@ function SessionHoverContent({ node, now, t }: { node: SessionNode; now: number;
  return (
    <div className={css.hoverContent}>
      <div className={css.hoverTitle}>{displayTitle(node, t)}</div>
-      <div className={css.hoverTime}>{hoverTimeLabel(node.updatedAt, now, t)}</div>
+      {/* Same placeholder rule as the row's trailing cell: no timestamp
+          before the first prompt. */}
+      {!node.blank && <div className={css.hoverTime}>{hoverTimeLabel(node.updatedAt, now, t)}</div>}
      <div className={css.hoverStatus}>
        <StateDot state={node.running ? 'ongoing' : 'done'} />
        <span>{node.running ? t('status.running') : t('status.idle')}</span>
@@ -243,7 +245,7 @@ function rowHalf(e: { clientY: number; currentTarget: HTMLElement }): 'before' |
  return e.clientY < rect.top + rect.height / 2 ? 'before' : 'after'
 }

-export function SessionNodeItem({ node, currentId, now, onOpen, onRename, onFork, drag, t }: {
+export function SessionNodeItem({ node, currentId, now, onOpen, onRename, onFork, onArchive, drag, t }: {
  node: SessionNode
  currentId: string | undefined
  now: number
@@ -252,6 +254,8 @@ export function SessionNodeItem({ node, currentId, now, onOpen, onRename, onFork
  onRename: (id: SessionNode['id'], currentTitle: string) => void
  /** Fork a session at its last completed turn (row menu action). */
  onFork: (id: SessionNode['id']) => void
+  /** Archive this session (row menu action; commits without a dialog). */
+  onArchive: (id: SessionNode['id']) => void
  /** Present only on draggable rows (workspace-group sessions outside search). */
  drag?: RowDragProps | undefined
  t: RowTranslate
@@ -260,10 +264,13 @@ export function SessionNodeItem({ node, currentId, now, onOpen, onRename, onFork
  const title = displayTitle(node, t)
  const selected = node.id === currentId
  const [menuOpen, setMenuOpen] = useState(false)
+  // Archive replaces the former Delete placeholder: it hides the row through
+  // the registry-global archive set and never touches the session log, so it
+  // is not styled as destructive and needs no confirmation dialog.
  const sessionMenuItems = [
    { id: 'rename', label: t('rename'), icon: <IconEditOutline16 /> },
    { id: 'fork', label: t('menu.fork'), icon: <IconBranchOutline16 /> },
-    { id: 'delete', label: t('menu.deleteSession'), icon: <IconTrashOutline16 />, danger: true },
+    { id: 'archive', label: t('menu.archiveSession'), icon: <IconDownloadOutline16 /> },
  ]
  // Figma session cell: pad 8, status slot 16, then a 4px title gap.
  const ownRow = (
@@ -301,31 +308,38 @@ export function SessionNodeItem({ node, currentId, now, onOpen, onRename, onFork
    >
      <span className={css.slot}>{row.running && <StateDot state="ongoing" />}</span>
      <span className={css.title}>{title}</span>
-      <span className={css.time}>{timeLabel(row.updatedAt, now, t)}</span>
-      <span className={css.rowActions}>
-        <Menu
-          open={menuOpen}
-          onClose={() => { setMenuOpen(false) }}
-          items={sessionMenuItems}
-          onSelect={(id) => {
-            setMenuOpen(false)
-            if (id === 'rename') onRename(node.id, row.title)
-            if (id === 'fork') onFork(node.id) // delete stays visual-only.
-          }}
-          portal
-          closeOnPointerLeave
-          anchor={(
-            <button
-              type="button"
-              className={css.iconButton}
-              aria-label={t('actions.session.aria', { name: title })}
-              onClick={(e) => { e.stopPropagation(); setMenuOpen(v => !v) }}
-            >
-              <IconEllipsisOutline16 />
-            </button>
-          )}
-        />
-      </span>
+      {/* A blank New Session row is a provisional placeholder: nothing has
+          happened in it yet, so a "now" timestamp and the row verbs
+          (rename/fork/archive) would all act on content that does not
+          exist — both trailing cells stay off until the first prompt. */}
+      {!row.blank && <span className={css.time}>{timeLabel(row.updatedAt, now, t)}</span>}
+      {!row.blank && (
+        <span className={css.rowActions}>
+          <Menu
+            open={menuOpen}
+            onClose={() => { setMenuOpen(false) }}
+            items={sessionMenuItems}
+            onSelect={(id) => {
+              setMenuOpen(false)
+              if (id === 'rename') onRename(node.id, row.title)
+              if (id === 'fork') onFork(node.id)
+              if (id === 'archive') onArchive(node.id)
+            }}
+            portal
+            closeOnPointerLeave
+            anchor={(
+              <button
+                type="button"
+                className={css.iconButton}
+                aria-label={t('actions.session.aria', { name: title })}
+                onClick={(e) => { e.stopPropagation(); setMenuOpen(v => !v) }}
+              >
+                <IconEllipsisOutline16 />
+              </button>
+            )}
+          />
+        </span>
+      )}
    </div>
  )
  return (
--- a/packages/client/ui-workspace/src/client/tree.ts
+++ b/packages/client/ui-workspace/src/client/tree.ts
@@ -90,9 +90,13 @@ function byRecency(a: SessionSummary, b: SessionSummary): number {
  return a.id < b.id ? -1 : 1
 }

-/** Ordinary sessions are visible; among blank sessions, only the current one is visible. */
-function sessionVisible(session: SessionSummary, current: SessionId | undefined): boolean {
-  return !session.blank || session.id === current
+/**
+ * Ordinary sessions are visible; among blank sessions, only the current one
+ * is visible; archived sessions are visible nowhere (their accounting slots
+ * remain, so unarchiving restores position).
+ */
+function sessionVisible(session: SessionSummary, current: SessionId | undefined, archived: ReadonlySet<SessionId>): boolean {
+  return !archived.has(session.id) && (!session.blank || session.id === current)
 }

 /**
@@ -126,7 +130,11 @@ function buildGroup(
 * order, with members resolved from sessionIds in their stored order. Sessions
 * outside every Workspace trail in the recency-ordered Ungrouped bucket.
 */
-function groupByWorkspace(list: SessionListState, workspaces: readonly WorkspaceView[]): Group[] {
+function groupByWorkspace(
+  list: SessionListState,
+  workspaces: readonly WorkspaceView[],
+  archived: ReadonlySet<SessionId>,
+): Group[] {
  const groups: Group[] = []
  const accounted = new Set<SessionId>()
  for (const workspace of workspaces) {
@@ -135,7 +143,7 @@ function groupByWorkspace(list: SessionListState, workspaces: readonly Workspace
      const summary = list.byId[id]
      if (summary === undefined) continue // account may lead the list pull; the row appears when the summary lands
      accounted.add(id)
-      if (!sessionVisible(summary, list.current)) continue
+      if (!sessionVisible(summary, list.current, archived)) continue
      members.push(summary)
    }
    groups.push(buildGroup(
@@ -146,7 +154,7 @@ function groupByWorkspace(list: SessionListState, workspaces: readonly Workspace
  const stray = list.ids
    .map(id => list.byId[id])
    .filter((s): s is SessionSummary =>
-      s !== undefined && !accounted.has(s.id) && sessionVisible(s, list.current))
+      s !== undefined && !accounted.has(s.id) && sessionVisible(s, list.current, archived))
  if (stray.length > 0) {
    groups.push(buildGroup(UNGROUPED_KEY, undefined, undefined, undefined, UNGROUPED_LABEL, stray, 'recency'))
  }
@@ -168,25 +176,29 @@ function sessionNode(s: SessionSummary): SessionNode {
 *
 * Every group shows; sessions populate under expanded groups, preserving
 * Host account order. Blank sessions are excluded except for the selected
- * provisional New Session row. Content search lives outside this derivation
+ * provisional New Session row; archived sessions are excluded everywhere.
+ * Content search lives outside this derivation
 * (see {@link deriveSearchResults}).
 * @param list - sessions list snapshot (`current` feeds containsCurrent).
 * @param workspaces - real workspaces in stable Host order.
+ * @param archivedSessionIds - registry-global archive set.
 * @param view - local expansion arrays.
 * @returns group sections in render order.
 */
 export function deriveGroups(
  list: SessionListState,
  workspaces: readonly WorkspaceView[],
+  archivedSessionIds: readonly SessionId[],
  view: TreeView,
 ): GroupNode[] {
+  const archived = new Set(archivedSessionIds)
  const expandedProjects = new Set(view.expandedProjects)
  const currentGroup = list.current === undefined
    ? undefined
    : (workspaces.find(w => w.sessionIds.includes(list.current as SessionId))?.workspaceId as string | undefined)
        ?? UNGROUPED_KEY
  const groups: GroupNode[] = []
-  for (const g of groupByWorkspace(list, workspaces)) {
+  for (const g of groupByWorkspace(list, workspaces, archived)) {
    const expanded = expandedProjects.has(g.key)
    groups.push({
      key: g.key,
@@ -209,13 +221,15 @@ export function deriveGroups(
 * no parent/child adjacency. Content search lives outside this derivation
 * (see {@link deriveSearchResults}).
 * @param list - sessions list snapshot.
+ * @param archivedSessionIds - registry-global archive set.
 * @returns flat rows in render order.
 */
-export function deriveFlat(list: SessionListState): SessionNode[] {
+export function deriveFlat(list: SessionListState, archivedSessionIds: readonly SessionId[]): SessionNode[] {
+  const archived = new Set(archivedSessionIds)
  const rows: SessionSummary[] = []
  for (const id of list.ids) {
    const s = list.byId[id]
-    if (s === undefined || !sessionVisible(s, list.current)) continue
+    if (s === undefined || !sessionVisible(s, list.current, archived)) continue
    rows.push(s)
  }
  rows.sort(byRecency)
@@ -238,6 +252,7 @@ export interface RelativeTime {
 * @param list - session metadata authority.
 * @param workspaces - Workspace membership and display labels.
 * @param query - caller text; surrounding whitespace is ignored.
+ * @param archivedSessionIds - registry-global archive set (members never match).
 * @param content - ranked Host content-search page.
 * @param limit - protocol-owned maximum merged row count.
 * @returns bounded deduplicated flat rows and a refine-query hint bit.
@@ -246,11 +261,13 @@ export function deriveSearchResults(
  list: SessionListState,
  workspaces: readonly WorkspaceView[],
  query: string,
+  archivedSessionIds: readonly SessionId[],
  content: { items: readonly SessionSearchResultItem[]; hasMore: boolean },
  limit: number,
 ): SearchResultSet {
  const q = query.trim().toLowerCase()
  if (q === '') return { items: [], hasMore: false }
+  const archived = new Set(archivedSessionIds)

  const workspaceBySession = new Map<SessionId, string>()
  for (const workspace of workspaces) {
@@ -270,7 +287,7 @@ export function deriveSearchResults(
    const summary = list.byId[id]
    // Blank placeholders never match a query (their canonical title displays
    // localized, so matching it would tie search to one language).
-    if (summary === undefined || summary.blank || !sessionVisible(summary, list.current)) continue
+    if (summary === undefined || summary.blank || !sessionVisible(summary, list.current, archived)) continue
    if (
      sessionTitle(summary).toLowerCase().includes(q)
      || labelOf(summary).toLowerCase().includes(q)
@@ -290,7 +307,7 @@ export function deriveSearchResults(
  for (const summary of local) include(summary)
  for (const item of content.items) {
    const summary = list.byId[item.sessionId]
-    if (summary !== undefined && !summary.blank && sessionVisible(summary, list.current)) include(summary)
+    if (summary !== undefined && !summary.blank && sessionVisible(summary, list.current, archived)) include(summary)
  }

  return {
--- a/packages/client/ui-workspace/tests/rows.spec.tsx
+++ b/packages/client/ui-workspace/tests/rows.spec.tsx
@@ -88,7 +88,7 @@ describe('workspace browser rows', () => {
    const onOpen = vi.fn()
    render(
      <SessionNodeItem node={node} currentId={node.id} now={0} onOpen={onOpen}
-        onRename={vi.fn()} onFork={vi.fn()} t={t} />,
+        onRename={vi.fn()} onFork={vi.fn()} onArchive={vi.fn()} t={t} />,
    )

    const row = screen.getByRole('treeitem')
@@ -157,18 +157,43 @@ describe('workspace browser rows', () => {
    expect(screen.queryByRole('button', { name: /工作区/ })).toBeNull()
  })

-  it('session row menu opens without opening the session and dispatches rename and fork', () => {
+  it('blank New Session rows carry no menu, no time label, and no hover-card time', () => {
+    vi.useFakeTimers()
+    try {
+      const node: SessionNode = {
+        id: sid('s-blank'), title: 'ignored', blank: true, running: false, updatedAt: 0,
+      }
+      render(<SessionNodeItem node={node} currentId={node.id} now={0} onOpen={vi.fn()}
+        onRename={vi.fn()} onFork={vi.fn()} onArchive={vi.fn()} t={t} />)
+      // The placeholder has no content yet: no row verbs, no "now" stamp.
+      expect(screen.queryByRole('button', { name: /会话.*的操作/ })).toBeNull()
+      expect(screen.queryByText('刚刚')).toBeNull()
+      // The hover card keeps title + status but drops the timestamp line.
+      const wrapper = screen.getByRole('treeitem').parentElement as HTMLElement
+      fireEvent.pointerEnter(wrapper)
+      act(() => { vi.advanceTimersByTime(500) })
+      expect(screen.getAllByText('新会话').length).toBeGreaterThanOrEqual(2)
+      expect(screen.getByText('空闲')).toBeTruthy()
+      expect(screen.queryByText('刚刚')).toBeNull()
+    } finally {
+      vi.useRealTimers()
+    }
+  })
+
+  it('session row menu opens without opening the session and dispatches rename, fork, and archive', () => {
    const onOpen = vi.fn()
    const onRename = vi.fn()
    const onFork = vi.fn()
+    const onArchive = vi.fn()
    const node: SessionNode = {
      id: sid('s1'), title: 'One', blank: false, running: false, updatedAt: 0,
    }
    render(<SessionNodeItem node={node} currentId={undefined} now={0} onOpen={onOpen}
-      onRename={onRename} onFork={onFork} t={t} />)
+      onRename={onRename} onFork={onFork} onArchive={onArchive} t={t} />)
    fireEvent.click(screen.getByRole('button', { name: '会话“One”的操作' }))
    expect(onOpen).not.toHaveBeenCalled()
-    expect(screen.getByRole('menuitem', { name: '删除会话' }).className).toMatch(/danger/)
+    // Archive is not destructive (log and accounting slot remain): no danger styling.
+    expect(screen.getByRole('menuitem', { name: '归档会话' }).className).not.toMatch(/danger/)
    // Rename dispatches with the current display title (dialog prefill).
    fireEvent.click(screen.getByRole('menuitem', { name: '重命名' }))
    expect(screen.queryByRole('menu')).toBeNull()
@@ -177,10 +202,12 @@ describe('workspace browser rows', () => {
    fireEvent.click(screen.getByRole('button', { name: '会话“One”的操作' }))
    fireEvent.click(screen.getByRole('menuitem', { name: '分叉会话' }))
    expect(onFork).toHaveBeenCalledWith(node.id)
-    // Delete stays visual-only.
+    // Archive dispatches without opening the session.
    fireEvent.click(screen.getByRole('button', { name: '会话“One”的操作' }))
-    fireEvent.click(screen.getByRole('menuitem', { name: '删除会话' }))
+    fireEvent.click(screen.getByRole('menuitem', { name: '归档会话' }))
+    expect(onArchive).toHaveBeenCalledWith(node.id)
    expect(onRename).toHaveBeenCalledOnce()
+    expect(onOpen).not.toHaveBeenCalled()
    // Escape closes without selecting (Menu onClose path).
    fireEvent.click(screen.getByRole('button', { name: '会话“One”的操作' }))
    fireEvent.keyDown(document, { key: 'Escape' })
@@ -194,7 +221,7 @@ describe('workspace browser rows', () => {
        id: sid('s1'), title: 'Hovered', blank: false, running: true, updatedAt: 0,
      }
      render(<SessionNodeItem node={node} currentId={undefined} now={60_000} onOpen={vi.fn()}
-        onRename={vi.fn()} onFork={vi.fn()} t={t} />)
+        onRename={vi.fn()} onFork={vi.fn()} onArchive={vi.fn()} t={t} />)
      const wrapper = screen.getByRole('treeitem').parentElement as HTMLElement
      fireEvent.pointerEnter(wrapper)
      act(() => { vi.advanceTimersByTime(500) })
@@ -220,7 +247,7 @@ describe('workspace browser rows', () => {
        id: sid('s1'), title: 'Quiet', blank: false, running: false, updatedAt: 0,
      }
      render(<SessionNodeItem node={node} currentId={undefined} now={0} onOpen={vi.fn()}
-        onRename={vi.fn()} onFork={vi.fn()} t={t} />)
+        onRename={vi.fn()} onFork={vi.fn()} onArchive={vi.fn()} t={t} />)
      fireEvent.pointerEnter(screen.getByRole('treeitem').parentElement as HTMLElement)
      act(() => { vi.advanceTimersByTime(500) })
      expect(screen.getByText('空闲')).toBeTruthy()
@@ -237,7 +264,7 @@ describe('workspace browser rows', () => {
    const inactive = dragProps()
    const { rerender } = render(
      <SessionNodeItem node={node} currentId={undefined} now={0} onOpen={vi.fn()}
-        onRename={vi.fn()} onFork={vi.fn()} drag={inactive} t={t} />,
+        onRename={vi.fn()} onFork={vi.fn()} onArchive={vi.fn()} drag={inactive} t={t} />,
    )
    const row = screen.getByRole('treeitem')
    stubRect(row)
@@ -255,7 +282,7 @@ describe('workspace browser rows', () => {
    const active = dragProps({ active: true, marker: 'before' })
    rerender(
      <SessionNodeItem node={node} currentId={undefined} now={0} onOpen={vi.fn()}
-        onRename={vi.fn()} onFork={vi.fn()} drag={active} t={t} />,
+        onRename={vi.fn()} onFork={vi.fn()} onArchive={vi.fn()} drag={active} t={t} />,
    )
    stubRect(screen.getByRole('treeitem'))
    // Top half hovers/drops 'before'; bottom half 'after' (row mid = 117).
@@ -269,7 +296,7 @@ describe('workspace browser rows', () => {
    const after = dragProps({ active: true, marker: 'after' })
    rerender(
      <SessionNodeItem node={node} currentId={undefined} now={0} onOpen={vi.fn()}
-        onRename={vi.fn()} onFork={vi.fn()} drag={after} t={t} />,
+        onRename={vi.fn()} onFork={vi.fn()} onArchive={vi.fn()} drag={after} t={t} />,
    )
    expect(screen.getByRole('treeitem').className).toMatch(/dropAfter/)
  })
--- a/packages/client/ui-workspace/tests/tree.spec.ts
+++ b/packages/client/ui-workspace/tests/tree.spec.ts
@@ -26,19 +26,21 @@ const workspace = (id: string, sessionIds: string[], title = id): WorkspaceView
 const view = (expandedProjects: readonly string[] = []) => ({
  expandedProjects,
 })
+const noArchive: readonly SessionId[] = []
+const archived = (...ids: string[]): readonly SessionId[] => ids.map(sid)

 describe('deriveGroups', () => {
  it('keeps Host Workspace and sessionIds order without Client recency sorting', () => {
    const sessions = list(summary('newer', 20), summary('older', 10))
    const workspaces = [workspace('first', ['older', 'newer']), workspace('empty', [])]
-    const groups = deriveGroups(sessions, workspaces, view(['first']))
+    const groups = deriveGroups(sessions, workspaces, noArchive, view(['first']))
    expect(groups.map(group => group.key)).toEqual(['first', 'empty'])
    expect(groups[0]!.sessions.map(session => session.id)).toEqual([sid('older'), sid('newer')])
  })

  it('puts only real unaccounted Sessions in the trailing Ungrouped group', () => {
    const sessions = list(summary('owned', 1, '/projects/first'), summary('loose', 9, '/other'))
-    const groups = deriveGroups(sessions, [workspace('first', ['owned'])], view([UNGROUPED_KEY]))
+    const groups = deriveGroups(sessions, [workspace('first', ['owned'])], noArchive, view([UNGROUPED_KEY]))
    expect(groups.map(group => group.key)).toEqual(['first', UNGROUPED_KEY])
    expect(groups[1]!.sessions.map(session => session.id)).toEqual([sid('loose')])
  })
@@ -52,7 +54,7 @@ describe('deriveGroups', () => {
      current: currentBlank.id,
    }
    const groups = deriveGroups(
-      sessions, [workspace('first', ['shown', 'current-blank', 'stale-blank'])], view(['first']),
+      sessions, [workspace('first', ['shown', 'current-blank', 'stale-blank'])], noArchive, view(['first']),
    )
    expect(groups[0]!.sessions.map(session => session.id)).toEqual([real.id, currentBlank.id])
    const blankNode = groups[0]!.sessions.find(session => session.id === currentBlank.id)!
@@ -63,7 +65,7 @@ describe('deriveGroups', () => {
    expect(groups[0]!.sessions.find(session => session.id === real.id)!.blank).toBe(false)
    expect(groups[0]!.sessionCount).toBe(2)
    // A non-current blank stray never surfaces an Ungrouped bucket either.
-    const strayGroups = deriveGroups(list({ ...summary('stray', 2), blank: true }), [workspace('first', [])], view())
+    const strayGroups = deriveGroups(list({ ...summary('stray', 2), blank: true }), [workspace('first', [])], noArchive, view())
    expect(strayGroups.map(group => group.key)).toEqual(['first'])
  })

@@ -80,6 +82,7 @@ describe('deriveGroups', () => {
    const groups = deriveGroups(
      list(parent, oldChild, newChild, tieB, tieA, self, orphan, cycleA, cycleB),
      [],
+      noArchive,
      { expandedProjects: [UNGROUPED_KEY] },
    )

@@ -90,7 +93,7 @@ describe('deriveGroups', () => {
    ])

    // Equal timestamps use ids as a deterministic tiebreak in either input order.
-    expect(deriveGroups(list(summary('tie-a', 1), summary('tie-b', 1)), [], view([UNGROUPED_KEY]))[0]!
+    expect(deriveGroups(list(summary('tie-a', 1), summary('tie-b', 1)), [], noArchive, view([UNGROUPED_KEY]))[0]!
      .sessions.map(node => node.id)).toEqual([sid('tie-a'), sid('tie-b')])
  })

@@ -100,17 +103,32 @@ describe('deriveGroups', () => {
      ids: [sid('present')],
      byId: { [sid('present')]: summary('present', 1) },
    }
-    const groups = deriveGroups(partial, [workspace('project', ['missing', 'present'])], view(['project']))
+    const groups = deriveGroups(partial, [workspace('project', ['missing', 'present'])], noArchive, view(['project']))
    expect(groups[0]!.sessions.map(node => node.id)).toEqual([sid('present')])
  })

+  it('hides archived sessions from workspace groups and Ungrouped', () => {
+    const kept = summary('kept', 1, '/projects/first')
+    const gone = summary('gone', 2, '/projects/first')
+    const looseGone = summary('loose-gone', 3, '/other')
+    const sessions = list(kept, gone, looseGone)
+    const groups = deriveGroups(
+      sessions, [workspace('first', ['kept', 'gone'])], archived('gone', 'loose-gone'), view(['first', UNGROUPED_KEY]),
+    )
+    // The archived member drops from its group AND the archived stray never
+    // surfaces an Ungrouped bucket; counts follow the visible rows.
+    expect(groups.map(group => group.key)).toEqual(['first'])
+    expect(groups[0]!.sessions.map(node => node.id)).toEqual([kept.id])
+    expect(groups[0]!.sessionCount).toBe(1)
+  })
+
  it('marks selected Workspace and Ungrouped sessions without relying on an Intent', () => {
    const owned = summary('owned', 1)
    const loose = summary('loose', 2)
    const ws = workspace('project', ['owned'])
-    const ownedGroups = deriveGroups({ ...list(owned, loose), current: owned.id }, [ws], view())
+    const ownedGroups = deriveGroups({ ...list(owned, loose), current: owned.id }, [ws], noArchive, view())
    expect(ownedGroups.find(group => group.key === 'project')!.containsCurrent).toBe(true)
-    const looseGroups = deriveGroups({ ...list(owned, loose), current: loose.id }, [ws], view())
+    const looseGroups = deriveGroups({ ...list(owned, loose), current: loose.id }, [ws], noArchive, view())
    expect(looseGroups.find(group => group.key === UNGROUPED_KEY)!.containsCurrent).toBe(true)
  })
 })
@@ -121,13 +139,13 @@ describe('deriveFlat', () => {
    const child = { ...summary('child', 30), parentId: parent.id }
    const tieB = summary('tie-b', 20)
    const tieA = summary('tie-a', 20)
-    const rows = deriveFlat(list(parent, child, tieB, tieA))
+    const rows = deriveFlat(list(parent, child, tieB, tieA), noArchive)
    expect(rows.map(row => row.id)).toEqual([sid('child'), sid('tie-a'), sid('tie-b'), sid('parent')])
  })

  it('tolerates ids whose summary has not landed yet', () => {
    const partial: SessionListState = { ...list(summary('present', 1)), ids: [sid('ghost'), sid('present')] }
-    expect(deriveFlat(partial).map(row => row.id)).toEqual([sid('present')])
+    expect(deriveFlat(partial, noArchive).map(row => row.id)).toEqual([sid('present')])
  })

  it('shows only the current blank session and excludes blanks from search', () => {
@@ -137,11 +155,35 @@ describe('deriveFlat', () => {
      ...list(summary('real', 1), currentBlank, staleBlank),
      current: currentBlank.id,
    }
-    const rows = deriveFlat(sessions)
+    const rows = deriveFlat(sessions, noArchive)
    expect(rows.map(row => row.id)).toEqual([currentBlank.id, sid('real')])
    expect(rows.map(row => row.title)).toEqual(['New Session', 'real'])
    expect(rows.map(row => row.blank)).toEqual([true, false])
  })
+
+  it('hides archived sessions in flat mode', () => {
+    const kept = summary('kept', 1)
+    const gone = summary('gone', 2)
+    expect(deriveFlat(list(kept, gone), archived('gone')).map(row => row.id)).toEqual([kept.id])
+  })
+})
+
+describe('deriveSearchResults archive filtering', () => {
+  it('archived sessions never match — not by title and not via a backend content hit', () => {
+    const hit = summary('hit', 2)
+    hit.displayTitle = 'Needle row'
+    const gone = summary('gone', 1)
+    gone.displayTitle = 'Needle archived'
+    const result = deriveSearchResults(
+      list(hit, gone),
+      [],
+      'needle',
+      archived('gone'),
+      { items: [{ sessionId: gone.id, snippet: 'needle body' }], hasMore: false },
+      10,
+    )
+    expect(result.items.map(item => item.id)).toEqual([hit.id])
+  })
 })

 describe('deriveSearchResults', () => {
@@ -160,6 +202,7 @@ describe('deriveSearchResults', () => {
        workspace('duplicate-owner', ['title-hit'], 'Ignored duplicate owner'),
      ],
      ' NEEDLE ',
+      noArchive,
      {
        items: [
          { sessionId: contentHit.id, snippet: 'body needle excerpt' },
@@ -212,6 +255,7 @@ describe('deriveSearchResults', () => {
      sessions,
      [workspace('first', ['opaque-current', 'new session stale'])],
      'new session',
+      noArchive,
      {
        items: [
          { sessionId: staleBlank.id, snippet: 'stale body' },
@@ -234,6 +278,7 @@ describe('deriveSearchResults', () => {
      list(...rows),
      [],
      'needle',
+      noArchive,
      { items: [], hasMore: false },
      3,
    )
@@ -244,12 +289,13 @@ describe('deriveSearchResults', () => {
      list(summary('body', 1)),
      [],
      'needle',
+      noArchive,
      { items: [{ sessionId: sid('body'), snippet: 'needle' }], hasMore: true },
      3,
    )
    expect(backendMore.items).toHaveLength(1)
    expect(backendMore.hasMore).toBe(true)
-    expect(deriveSearchResults(list(), [], '  ', { items: [], hasMore: true }, 3))
+    expect(deriveSearchResults(list(), [], '  ', noArchive, { items: [], hasMore: true }, 3))
      .toEqual({ items: [], hasMore: false })
  })
 })
--- a/packages/client/ui-workspace/tests/workspace-browser.spec.tsx
+++ b/packages/client/ui-workspace/tests/workspace-browser.spec.tsx
@@ -35,8 +35,8 @@ const workspace = (id: string, sessionIds: string[], title = id): WorkspaceView
  workspaceId: wid(id), path: `/projects/${id}`, title,
  sessionIds: sessionIds.map(sid), createdAt: '2026-01-01T00:00:00.000Z', updatedAt: '2026-01-01T00:00:00.000Z',
 })
-const workspaceState = (items: readonly WorkspaceView[]): WorkspaceListState => ({
-  items, state: 'idle', phase: 'ready', error: null, baselinesReady: true,
+const workspaceState = (items: readonly WorkspaceView[], archivedSessionIds: readonly SessionId[] = []): WorkspaceListState => ({
+  items, archivedSessionIds, state: 'idle', phase: 'ready', error: null, baselinesReady: true,
  recentWorkspaceId: items[0]?.workspaceId,
 })
 function hook<T>(snapshot: T) {
@@ -68,6 +68,7 @@ function mount(overrides: Partial<WorkspaceBrowserProps> = {}) {
    forkSession: vi.fn(),
    renameWorkspace: vi.fn(async () => {}),
    deleteWorkspace: vi.fn(async () => {}),
+    archiveSession: vi.fn(async () => {}),
    insertSessionBefore: vi.fn(async () => {}),
    createWorkspace: vi.fn(async () => workspace('created', [])),
    useDirectoryFlow: bindSnapshotSelector({ getSnapshot: () => true, subscribe: () => () => {} }),
@@ -135,6 +136,50 @@ describe('WorkspaceBrowser', () => {
    expect(screen.queryByText('alpha-s')).toBeNull()
  })

+  it('archives a session from the row menu and hides archived rows in both modes', async () => {
+    const archiveSession = vi.fn(async () => {})
+    const b = mount({
+      useSessions: hook(sessionState([summary('kept-s', 2), summary('gone-s', 1)])),
+      useWorkspaces: hook(workspaceState([workspace('alpha', ['kept-s', 'gone-s'])])),
+      archiveSession,
+    })
+    fireEvent.click(screen.getByText('alpha'))
+    fireEvent.click(screen.getByRole('button', { name: '会话“gone-s”的操作' }))
+    fireEvent.click(screen.getByRole('menuitem', { name: '归档会话' }))
+    expect(archiveSession).toHaveBeenCalledWith(sid('gone-s'))
+
+    // The archive-set echo hides the row in grouped mode (count included) and flat mode.
+    rerender(b, { useWorkspaces: hook(workspaceState([workspace('alpha', ['kept-s', 'gone-s'])], [sid('gone-s')])) })
+    expect(screen.queryByText('gone-s')).toBeNull()
+    expect(screen.getByText('1 个会话')).toBeTruthy()
+    fireEvent.click(screen.getByRole('button', { name: '分组方式' }))
+    fireEvent.click(screen.getByRole('menuitem', { name: '单列表' }))
+    expect(screen.getByText('kept-s')).toBeTruthy()
+    expect(screen.queryByText('gone-s')).toBeNull()
+  })
+
+  it('logs and keeps the tree when the archive call rejects', async () => {
+    const rejection = new Error('archive exploded')
+    const archiveSession = vi.fn(async () => { throw rejection })
+    const warn = vi.spyOn(console, 'warn').mockImplementation(() => {})
+    try {
+      mount({
+        useSessions: hook(sessionState([summary('alpha-s', 1)])),
+        useWorkspaces: hook(workspaceState([workspace('alpha', ['alpha-s'])])),
+        archiveSession,
+      })
+      fireEvent.click(screen.getByText('alpha'))
+      fireEvent.click(screen.getByRole('button', { name: '会话“alpha-s”的操作' }))
+      fireEvent.click(screen.getByRole('menuitem', { name: '归档会话' }))
+      await Promise.resolve()
+      await Promise.resolve()
+      expect(warn).toHaveBeenCalledWith('session archive rejected:', rejection)
+      expect(screen.getByText('alpha-s')).toBeTruthy()
+    } finally {
+      warn.mockRestore()
+    }
+  })
+
  it('renders a fork child as a top-level row without a session twist', () => {
    const parent = summary('parent-s', 2)
    const child = { ...summary('child-s', 1), parentId: parent.id }
--- a/packages/client/ui-workspace/tests/workspace-picker.spec.tsx
+++ b/packages/client/ui-workspace/tests/workspace-picker.spec.tsx
@@ -32,7 +32,7 @@ const sessions: SessionListState = {
  ids: [], byId: {}, current: undefined, phase: 'ready',
 }
 const workspaceState = (items: readonly WorkspaceView[]): WorkspaceListState => ({
-  items, state: 'idle', phase: 'ready', error: null, baselinesReady: true,
+  items, archivedSessionIds: [], state: 'idle', phase: 'ready', error: null, baselinesReady: true,
  recentWorkspaceId: items[0]?.workspaceId,
 })
 function anchor(): { current: HTMLElement } {
--- a/packages/cordis/tool-cordis/src/api-catalog.ts
+++ b/packages/cordis/tool-cordis/src/api-catalog.ts
@@ -1162,6 +1162,10 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
        signature: 'delete(id: WorkspaceId): Promise<boolean>',
        jsDoc: '/**\n * Delete one workspace registration while retaining its directory and every\n * session log. The durable order is updated before the table deletion; a\n * failed table write restores the prior order and keeps the entity\n * published. Unknown ids are an idempotent no-op for domain callers.\n * @param id - Workspace registration to remove.\n * @returns `true` when a record was deleted, `false` when it was unknown.\n */',
      },
+      {
+        signature: 'archiveSession(sessionId: SessionId): Promise<void>',
+        jsDoc: '/**\n * Archive one session durably. The session must exist (live or in session\n * persistence); its workspace accounting — or lack of one — is irrelevant.\n * An already archived id resolves without writing.\n * @param sessionId - The session to archive.\n * @returns resolution after durability.\n */',
+      },
      {
        signature: 'async resolveByPath(path: string): Promise<Workspace | undefined>',
        jsDoc: '/**\n * Resolve by canonical directory path without creating or mutating a\n * workspace. A missing path rejects during `realpath`; an existing unowned\n * directory returns `undefined`.\n * @param path - Existing directory path in any spelling.\n * @returns the workspace owning the canonical path, when one exists.\n */',
@@ -2207,6 +2211,14 @@ export const TYPE_API: readonly TypeApiEntry[] = [
    name: 'PtyWaitReason',
    declaration: 'export type PtyWaitReason = \'stdin_read\' | \'inferred_idle\' | \'timeout\' | \'session_exit\';',
  },
+  {
+    name: 'ReadFileLine',
+    declaration: 'export interface ReadFileLine {\n    number: number;\n    text: string;\n}',
+  },
+  {
+    name: 'ReadResultView',
+    declaration: 'export interface ReadResultView {\n    card: \'read\';\n    title?: string;\n    path: string;\n    offset: number;\n    lines: ReadFileLine[];\n    totalLines: number;\n    lang?: string;\n    content?: ContentBlock[];\n}',
+  },
  {
    name: 'ReasoningBlock',
    declaration: 'export interface ReasoningBlock {\n    type: \'reasoning\';\n    text: string;\n}',
@@ -2845,7 +2857,7 @@ export const TYPE_API: readonly TypeApiEntry[] = [
  },
  {
    name: 'ToolResultView',
-    declaration: 'export type ToolResultView = GenericResultView | TerminalResultView | DiffResultView | WebResultView;',
+    declaration: 'export type ToolResultView = GenericResultView | TerminalResultView | DiffResultView | ReadResultView | WebResultView;',
  },
  {
    name: 'ToolRunContext',
--- a/packages/core/tools/README.i18n.yaml
+++ b/packages/core/tools/README.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/core/tools/README.md
-README.md: e7f395f8c1d6417db856e590f5267cf6887e4d12
-README.zh.md: acb4c047bf86e36c828882ff751d4be1f627f99e
+README.md: dcce455f9551318f3871e3df84c29789078fef7c
+README.zh.md: 63eaa2e0b66797c74a1d4845c29ca970b63f5f99
--- a/packages/core/tools/README.md
+++ b/packages/core/tools/README.md
@@ -108,7 +108,7 @@ Optional `isConcurrencySafe(args)` receives typed, softly validated arguments. E
 Tools optionally own pure `presentCall()` and `presentResult()` render intents, so UIs do not special-case tool names:

 - Call views are `{ card: 'generic', title, kind?, rawInput?, content?, locations? }`, `{ card: 'terminal', title, description?, cwd? }`, or `{ card: 'diff', title, diffs, locations? }`.
- Result views are `{ card: 'generic', title?, content? }`, `{ card: 'terminal', title?, output?, exitCode?, signal? }`, `{ card: 'diff', title?, diffs }`, or `{ card: 'web', kind: 'search' | 'fetch', title?, … }` (a completed web retrieval; the `kind` arms carry the structured search sources or the fetch summary, and a UI without the `web` capability falls back to the raw result content).
+- Result views are `{ card: 'generic', title?, content? }`, `{ card: 'terminal', title?, output?, exitCode?, signal? }`, `{ card: 'diff', title?, diffs }`, `{ card: 'read', title?, path, offset, lines, totalLines, lang?, content? }` (a completed file read → a line-numbered, optionally syntax-highlighted code view; `offset` is the 1-based first line the window requested, kept even when `lines` is empty; `lines` is `{ number, text }[]` keeping each file line number, and `content` is the envelope-stripped text a UI without read support falls back to), or `{ card: 'web', kind: 'search' | 'fetch', title?, … }` (a completed web retrieval; the `kind` arms carry the structured search sources or the fetch summary, and a UI without the `web` capability falls back to the raw result content).

 Returning `undefined` selects generic fallback. Presenters depend only on their arguments and the durable result because UIs call them during live streaming and log replay. `output.presentationMeta(args, value)` derives JSON metadata for direct surface calls; that metadata persists with `tool/result` and returns to `presentResult`, while the canonical value itself remains execution-local and is never replayed. Nested Code dispatches do not compute metadata. `defineTool` soft-validates older logged arguments and falls back instead of crashing replay. `dsh-tool-bash` and `dsh-tool-fs` are the reference implementations; the [canonical-output Agent Note](../../../.agents/notes/implemented/architecture/2026-07-20-canonical-tool-output-contract.md) owns the value/presentation split and the [render-intent Agent Note](../../../.agents/notes/implemented/architecture/2026-07-02-tool-render-intent-union.md) owns card vocabulary.

--- a/packages/core/tools/README.zh.md
+++ b/packages/core/tools/README.zh.md
@@ -108,7 +108,7 @@ ctx.tools.register(defineTool({
 工具可以选择拥有纯 `presentCall()` 和 `presentResult()` 呈现意图，使 UI 无需特殊处理工具名称：

 - 调用视图为 `{ card: 'generic', title, kind?, rawInput?, content?, locations? }`、`{ card: 'terminal', title, description?, cwd? }` 或 `{ card: 'diff', title, diffs, locations? }`。
- 结果视图为 `{ card: 'generic', title?, content? }`、`{ card: 'terminal', title?, output?, exitCode?, signal? }`、`{ card: 'diff', title?, diffs }` 或 `{ card: 'web', kind: 'search' | 'fetch', title?, … }`（已完成的 web 检索；`kind` 各分支携带结构化的搜索来源或抓取摘要，不具备 `web` 能力的 UI 回退到原始结果内容）。
+- 结果视图为 `{ card: 'generic', title?, content? }`、`{ card: 'terminal', title?, output?, exitCode?, signal? }`、`{ card: 'diff', title?, diffs }`、`{ card: 'read', title?, path, offset, lines, totalLines, lang?, content? }`（已完成的文件读取→带行号、可选语法高亮的代码视图；`offset` 是窗口请求的 1-based 起始行，即使 `lines` 为空也保留；`lines` 是 `{ number, text }[]`，保留每一行的文件行号，`content` 是无读取能力的 UI 回退时使用的去信封文本）或 `{ card: 'web', kind: 'search' | 'fetch', title?, … }`（已完成的 web 检索；`kind` 各分支携带结构化的搜索来源或抓取摘要，不具备 `web` 能力的 UI 回退到原始结果内容）。

 返回 `undefined` 会选择通用回退。呈现器只依赖其参数和持久结果，因为 UI 会在实时流式输出和日志回放期间调用它们。`output.presentationMeta(args, value)` 为直接接口调用派生 JSON 元数据；该元数据随 `tool/result` 持久化并传回 `presentResult`，而规范值本身仍只存在于执行局部，绝不会回放。嵌套 Code 分发不会计算元数据。`defineTool` 会软验证较旧的日志参数并回退，而不会使回放崩溃。`dsh-tool-bash` 与 `dsh-tool-fs` 是参考实现；[规范输出 Agent Note](../../../.agents/notes/implemented/architecture/2026-07-20-canonical-tool-output-contract.md) 规定值／呈现拆分，[呈现意图 Agent Note](../../../.agents/notes/implemented/architecture/2026-07-02-tool-render-intent-union.md) 规定卡片词汇。

--- a/packages/core/tools/src/index.ts
+++ b/packages/core/tools/src/index.ts
@@ -74,6 +74,7 @@ export type {
  ToolCallKind,
  FileLocation,
  FileDiff,
+  ReadFileLine,
  ToolCallView,
  GenericCallView,
  TerminalCallView,
@@ -82,6 +83,7 @@ export type {
  GenericResultView,
  TerminalResultView,
  DiffResultView,
+  ReadResultView,
  WebResultView,
  WebSearchResultView,
  WebFetchResultView,
--- a/packages/core/tools/src/presentation.ts
+++ b/packages/core/tools/src/presentation.ts
@@ -117,6 +117,18 @@ export interface DiffCallView {
  locations?: FileLocation[]
 }

+/**
+ * One numbered line of a file, the unit a {@link ReadResultView} carries so a
+ * capable UI can render a syntax-highlighted, line-numbered code view. `number`
+ * is the 1-based line number in the file (a window past `offset` keeps the file's
+ * own numbering, not a 1-based re-count); `text` is the line without its trailing
+ * newline, already truncated to the read tool's per-line cap.
+ */
+export interface ReadFileLine {
+  number: number
+  text: string
+}
+
 /**
 * How a tool wants the COMPLETED call shown — the *result* state, after `execute`
 * returns. A `card`-tagged union mirroring {@link ToolCallView}: a UI switches on
@@ -125,7 +137,7 @@ export interface DiffCallView {
 * `ToolDefinition.presentResult`; omitting the method keeps the pending
 * title and renders the raw result content.
 */
-export type ToolResultView = GenericResultView | TerminalResultView | DiffResultView | WebResultView
+export type ToolResultView = GenericResultView | TerminalResultView | DiffResultView | ReadResultView | WebResultView

 /**
 * The default completed card: an optional replacement title and reformatted
@@ -177,6 +189,47 @@ export interface DiffResultView {
  diffs: FileDiff[]
 }

+/**
+ * A completed file read rendered as a line-numbered, optionally syntax-highlighted
+ * code view by a capable UI. Set by a tool whose call reads file text (e.g.
+ * `read`); the pending state stays a {@link GenericCallView} (`kind: 'read'`)
+ * because a call carries no content until `execute` returns. The structured
+ * `lines`/`path`/`lang`/`totalLines` fields cannot be reconstructed from the
+ * model-facing result text alone, so the read tool projects them through its
+ * `output.presentationMeta` (persisted with the session log) and `presentResult`
+ * narrows that metadata back into this view on live and replay paths alike. A UI
+ * without the read capability falls back to `content` (the model-facing text with
+ * its envelope stripped), so this view degrades to the generic text card.
+ */
+export interface ReadResultView {
+  card: 'read'
+  /** Replacement title for the completed call. Omit to keep the pending-state title. */
+  title?: string
+  /** The read file's path (the model-facing path; the bridge relativizes it). */
+  path: string
+  /**
+   * The 1-based first line the window requested, preserved even when `lines` is
+   * empty (a byte cap below the first selected line yields an empty window) so a
+   * UI knows where the window starts and where a continuation resumes.
+   */
+  offset: number
+  /** The returned window's lines, in file order, each keeping its file line number. */
+  lines: ReadFileLine[]
+  /** Exact total line count in the file, so a UI can show a "showing N of M" affordance. */
+  totalLines: number
+  /**
+   * A syntax-highlighting language hint derived from the file extension (e.g.
+   * `ts`, `py`), or omitted when the extension maps to no known language so a UI
+   * renders the lines as plain text.
+   */
+  lang?: string
+  /**
+   * The model-facing result content with its envelope stripped, for a UI without
+   * the read capability. Omit to let such a UI render the raw result content.
+   */
+  content?: ContentBlock[]
+}
+
 /**
 * One citeable source in a completed {@link WebSearchResultView}, the faithful
 * projection of one web-search source. The presentation projection of `dsh-web`'s
--- a/packages/fs/tool-fs/README.i18n.yaml
+++ b/packages/fs/tool-fs/README.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/fs/tool-fs/README.md
-README.md: 4ff9b043525e8e7a0b59e3d91410951d88bb9a69
-README.zh.md: ce93e10072d74ce268273aa472bfbb3f34f46259
+README.md: c00b59fed06249e6d9479c4a809cdf7d78f93239
+README.zh.md: f90fbb36391c1388ab0f6836daa2a9061d046be6
--- a/packages/fs/tool-fs/README.md
+++ b/packages/fs/tool-fs/README.md
@@ -34,7 +34,7 @@ All keys are optional; the defaults are the shipped read caps.

 Field names are snake_case to match Claude Code and existing harness tool schemas.

-Canonical successes are `read` → `{ path, offset, lines: [{ number, text }], totalLines }`, `write` → `{ path, operation: 'create' | 'update', before: string | null, after }`, and `edit` → `{ path, before, after }`. Native renderers preserve the line-numbered read and mutation acknowledgements below. Write/edit derive replayable diff-card metadata from these values; the values themselves are execution-local and are not added to `tool/result`.
+Canonical successes are `read` → `{ path, offset, lines: [{ number, text }], totalLines }`, `write` → `{ path, operation: 'create' | 'update', before: string | null, after }`, and `edit` → `{ path, before, after }`. Native renderers preserve the line-numbered read and mutation acknowledgements below. `write`/`edit` derive replayable diff-card metadata, and `read` derives a replayable read-card window `{ path, offset, lines, totalLines, lang? }`, from these canonical values; the canonical values themselves are execution-local and are not added to `tool/result`, only the derived presentation metadata is persisted.

 ## The tool is the executor; policy is an event gate

--- a/packages/fs/tool-fs/README.zh.md
+++ b/packages/fs/tool-fs/README.zh.md
@@ -34,7 +34,7 @@ await ctx.plugin(ToolFs)                                  // this package — re

 字段名使用 snake_case，与 Claude Code 和现有 harness 工具 schema 一致。

-规范成功值分别为：`read` → `{ path, offset, lines: [{ number, text }], totalLines }`，`write` → `{ path, operation: 'create' | 'update', before: string | null, after }`，`edit` → `{ path, before, after }`。原生渲染器会保留下方带行号的读取结果和变更确认。写入/编辑从这些值派生可回放的 diff 卡片元数据；这些值本身仅限于本次执行，不会添加到 `tool/result`。
+规范成功值分别为：`read` → `{ path, offset, lines: [{ number, text }], totalLines }`，`write` → `{ path, operation: 'create' | 'update', before: string | null, after }`，`edit` → `{ path, before, after }`。原生渲染器会保留下方带行号的读取结果和变更确认。`write`/`edit` 从这些规范值派生可回放的 diff 卡片元数据，`read` 派生可回放的读取卡片窗口 `{ path, offset, lines, totalLines, lang? }`；规范值本身仅限于本次执行，不会添加到 `tool/result`，只有派生出的呈现元数据会被持久化。

 ## 工具就是执行器；策略是事件门禁

--- a/packages/fs/tool-fs/src/read-render.ts
+++ b/packages/fs/tool-fs/src/read-render.ts
@@ -168,3 +168,105 @@ export function formatReadOutput(displayPath: string, outcome: FileReadOutcome):
 ${body}
 </content>`
 }
+
+/**
+ * Lowercased file-extension to syntax-highlighting language hint. Keys are the
+ * extension without its dot; a UI treats an absent key as plain text. The map is
+ * intentionally small — common source, config, and markup extensions a
+ * line-numbered code view benefits from highlighting — not an exhaustive registry.
+ */
+const LANG_BY_EXTENSION: Readonly<Record<string, string>> = {
+  ts: 'ts', tsx: 'tsx', mts: 'ts', cts: 'ts',
+  js: 'js', jsx: 'jsx', mjs: 'js', cjs: 'js',
+  json: 'json', jsonc: 'json',
+  py: 'py', rb: 'rb', go: 'go', rs: 'rs', java: 'java',
+  c: 'c', h: 'c', cc: 'cpp', cpp: 'cpp', hpp: 'cpp', cxx: 'cpp',
+  cs: 'cs', kt: 'kotlin', swift: 'swift', php: 'php',
+  sh: 'sh', bash: 'sh', zsh: 'sh',
+  yaml: 'yaml', yml: 'yaml', toml: 'toml', ini: 'ini',
+  md: 'md', markdown: 'md', mdx: 'mdx',
+  html: 'html', htm: 'html', css: 'css', scss: 'scss', less: 'less',
+  sql: 'sql', xml: 'xml', lua: 'lua',
+}
+
+/**
+ * Derive a syntax-highlighting language hint from a read path's file extension.
+ * Pure and case-insensitive on the extension; a dotfile with no extension
+ * (`.gitignore`) and an unknown extension both yield `undefined`.
+ * @param path - the model-facing path the read reported.
+ * @returns the language hint for {@link LANG_BY_EXTENSION}, or `undefined` when the extension maps to none.
+ */
+export function langFromPath(path: string): string | undefined {
+  const base = path.slice(Math.max(path.lastIndexOf('/'), path.lastIndexOf('\\')) + 1)
+  const dot = base.lastIndexOf('.')
+  // A leading dot is a dotfile (no extension), not an empty extension.
+  if (dot <= 0) return undefined
+  const ext = base.slice(dot + 1).toLowerCase()
+  // Own-property check only: a filename whose extension is an Object.prototype
+  // key (`foo.constructor`, `foo.__proto__`) must map to no language, not to the
+  // inherited member — otherwise a function would reach `lang` and fail the
+  // tool-output JSON validation.
+  return Object.hasOwn(LANG_BY_EXTENSION, ext) ? LANG_BY_EXTENSION[ext] : undefined
+}
+
+/**
+ * The `read` tool's private `tool/result` `meta` payload: the structured
+ * line-numbered window a capable UI renders as a code view. Attached opaquely (as
+ * `unknown`) on the tool result and persisted with the session log — it must be
+ * JSON-serializable (the session validates this at `append`), so `presentResult`
+ * reproduces the read card on replay when the raw structured output is no longer
+ * on the wire. The producing tool owns and narrows this opaque shape.
+ */
+export interface FsReadMeta {
+  /** The read file's model-facing path. */
+  path: string
+  /** The 1-based first line the window requested, kept even when `lines` is empty. */
+  offset: number
+  /** The returned window's lines, each keeping its file line number. */
+  lines: FileTextLine[]
+  /** Exact total line count in the file. */
+  totalLines: number
+  /** Syntax-highlighting language hint from the extension, or omitted for plain text. */
+  lang?: string
+}
+
+/**
+ * Whether `value` is a valid {@link FileTextLine} (defensive narrowing from
+ * opaque `meta`). `number` must be a 1-based integer line number, since a card
+ * rendered from a zero, fractional, or non-finite line number would violate the
+ * 1-based numbering contract the read window promises.
+ */
+function isFileTextLine(value: unknown): value is FileTextLine {
+  if (typeof value !== 'object' || value === null || Array.isArray(value)) return false
+  const { number, text } = value as Record<string, unknown>
+  return typeof number === 'number' && Number.isInteger(number) && number >= 1 && typeof text === 'string'
+}
+
+/**
+ * Narrow opaque live or replayed result metadata to a structured read window.
+ * Malformed metadata returns `undefined` so presentation can fall back to the
+ * generic text card instead of throwing during replay. Beyond shape, the
+ * semantic contract of a read window is enforced against replayed JSON that is
+ * well-typed but out of range: `offset` must be a 1-based integer, `totalLines`
+ * must be a non-negative integer, each line number must be a 1-based integer no
+ * less than `offset`, the line numbers must strictly increase, and no line number
+ * may exceed `totalLines`. Any violation declines to the generic fallback rather
+ * than emitting a card that misnumbers or overcounts.
+ * @param meta - result metadata.
+ * @returns the validated read window, or `undefined` for absent, malformed, or semantically invalid data.
+ */
+export function readMetaFromMeta(meta: unknown): FsReadMeta | undefined {
+  if (typeof meta !== 'object' || meta === null || Array.isArray(meta)) return undefined
+  const { path, offset, lines, totalLines, lang } = meta as Record<string, unknown>
+  if (typeof path !== 'string' || typeof totalLines !== 'number' || typeof offset !== 'number') return undefined
+  if (!Number.isInteger(offset) || offset < 1) return undefined
+  if (!Number.isInteger(totalLines) || totalLines < 0) return undefined
+  if (!Array.isArray(lines) || !lines.every(isFileTextLine)) return undefined
+  if (lang !== undefined && typeof lang !== 'string') return undefined
+  let previous = offset - 1
+  for (const { number } of lines) {
+    if (number <= previous || number > totalLines) return undefined
+    previous = number
+  }
+  return { path, offset, lines, totalLines, ...lang === undefined ? {} : { lang } }
+}
--- a/packages/fs/tool-fs/src/read.ts
+++ b/packages/fs/tool-fs/src/read.ts
@@ -6,11 +6,11 @@

 import type { Context } from 'cordis'
 import { defineTool } from '@deepseek-ai/dsh-tools'
-import type { GenericCallView, GenericResultView, ToolResult } from '@deepseek-ai/dsh-tools'
+import type { GenericCallView, ReadResultView, ToolResult } from '@deepseek-ai/dsh-tools'
 import { FsError } from '@deepseek-ai/dsh-fs'
 import type {} from '@deepseek-ai/dsh-fs'
 import type {} from '@deepseek-ai/dsh-system-prompt'
-import { buildWindow, formatReadOutput } from './read-render.ts'
+import { buildWindow, formatReadOutput, langFromPath, readMetaFromMeta } from './read-render.ts'
 import { sessionResolveOptions } from './session-cwd.ts'

 /** Default and maximum number of lines returned by one `read` call (the `readLimit` config). */
@@ -118,6 +118,19 @@ export function applyReadTool(ctx: Context, caps: ReadToolCaps): void {
          }),
        }]
      },
+      // Project the structured window into persisted `meta` so a UI's read card
+      // survives replay: the raw canonical output object is not on the wire, only
+      // the model-facing text, from which the line/lang data cannot be recovered.
+      presentationMeta: (_args, value) => {
+        const lang = langFromPath(value.path)
+        return {
+          path: value.path,
+          offset: value.offset,
+          lines: value.lines.map(({ number, text }) => ({ number, text })),
+          totalLines: value.totalLines,
+          ...lang === undefined ? {} : { lang },
+        }
+      },
    },
    // Observation races fail closed because guarded mutations re-check the version in-lock.
    isConcurrencySafe: () => true,
@@ -154,15 +167,32 @@ export function applyReadTool(ctx: Context, caps: ReadToolCaps): void {
      ctx.emit('fs/observed', target, info.version, exec)
      return outcome
    },
-    presentResult(_args, result: ToolResult): GenericResultView | undefined {
+    // Result-time display: a `read` card carrying the structured line window a
+    // capable UI renders as a line-numbered, syntax-highlighted view. The
+    // structured data is narrowed from the persisted `meta` (replay-safe); the
+    // envelope-stripped model-facing text rides along as `content` so a UI without
+    // the read capability still shows the file text. A malformed or absent meta,
+    // or a result whose text is not the read envelope, declines to `undefined`
+    // (the generic fallback), never throwing on replay of obsolete logged output.
+    presentResult(_args, result: ToolResult): ReadResultView | undefined {
      if (result.isError) return undefined
+      const meta = readMetaFromMeta(result.meta)
+      if (meta === undefined) return undefined
      const only = result.content.length === 1 ? result.content[0] : undefined
      const text = only?.type === 'text' ? only.text : undefined
      if (text === undefined) return undefined
      // Group 1 always captures (possibly empty) when the envelope matches.
      const body = /^<path>[^\n]*<\/path>\n<type>file<\/type>\n<content>\n([\s\S]*)\n<\/content>$/u.exec(text)?.[1]
      if (body === undefined) return undefined
-      return { card: 'generic', content: [{ type: 'text', text: body }] }
+      return {
+        card: 'read',
+        path: meta.path,
+        offset: meta.offset,
+        lines: meta.lines,
+        totalLines: meta.totalLines,
+        ...meta.lang === undefined ? {} : { lang: meta.lang },
+        content: [{ type: 'text', text: body }],
+      }
    },
    // Pure display: a generic card titled by the file with the read window appended (`Read
    // foo.txt (5 - 8)`), `read` kind (icon), and a follow-along location whose line is the
--- a/packages/fs/tool-fs/tests/read-render.spec.ts
+++ b/packages/fs/tool-fs/tests/read-render.spec.ts
@@ -6,7 +6,7 @@
 */

 import { describe, expect, it } from 'vitest'
-import { buildWindow, READ_MAX_BYTES, READ_MAX_LINE_LENGTH } from '../src/read-render.ts'
+import { buildWindow, langFromPath, readMetaFromMeta, READ_MAX_BYTES, READ_MAX_LINE_LENGTH } from '../src/read-render.ts'
 import type { ReadWindow } from '../src/read-render.ts'

 const DEFAULT_CAPS = { maxLineLength: READ_MAX_LINE_LENGTH, maxBytes: READ_MAX_BYTES }
@@ -116,3 +116,103 @@ describe('buildWindow', () => {
    })
  })
 })
+
+describe('langFromPath', () => {
+  it('maps a known extension to its language hint, case-insensitively', () => {
+    expect(langFromPath('src/a.ts')).toBe('ts')
+    expect(langFromPath('src/a.TSX')).toBe('tsx')
+    expect(langFromPath('/abs/module.mjs')).toBe('js')
+    expect(langFromPath('conf.yml')).toBe('yaml')
+    expect(langFromPath('README.md')).toBe('md')
+  })
+
+  it('reads the extension after the last path segment and last dot', () => {
+    expect(langFromPath('a.py.bak')).toBeUndefined()
+    expect(langFromPath('archive.tar.gz')).toBeUndefined()
+    expect(langFromPath('/dir.py/plain')).toBeUndefined()
+    expect(langFromPath('C:\\src\\main.rs')).toBe('rs')
+  })
+
+  it('returns undefined for a dotfile, an extensionless name, and an unknown extension', () => {
+    expect(langFromPath('.gitignore')).toBeUndefined()
+    expect(langFromPath('/etc/hosts')).toBeUndefined()
+    expect(langFromPath('data.unknownext')).toBeUndefined()
+    expect(langFromPath('trailingdot.')).toBeUndefined()
+  })
+
+  it('returns undefined for a filename whose extension is an Object.prototype key', () => {
+    // Own-property lookup only: these must not resolve to the inherited member
+    // (a function/object), which would fail the tool-output JSON validation.
+    expect(langFromPath('foo.constructor')).toBeUndefined()
+    expect(langFromPath('foo.__proto__')).toBeUndefined()
+    expect(langFromPath('foo.toString')).toBeUndefined()
+    expect(langFromPath('foo.hasOwnProperty')).toBeUndefined()
+  })
+})
+
+describe('readMetaFromMeta', () => {
+  const good = { path: '/abs/a.ts', offset: 1, lines: [{ number: 1, text: 'x' }], totalLines: 1, lang: 'ts' }
+
+  it('narrows a well-formed read meta, with and without a lang hint', () => {
+    expect(readMetaFromMeta(good)).toEqual(good)
+    const noLang = { path: '/abs/a', offset: 1, lines: [], totalLines: 0 }
+    expect(readMetaFromMeta(noLang)).toEqual(noLang)
+  })
+
+  it('narrows an empty window at a positive offset (byte cap below the first selected line)', () => {
+    const empty = { path: '/abs/a', offset: 5, lines: [], totalLines: 9 }
+    expect(readMetaFromMeta(empty)).toEqual(empty)
+  })
+
+  it('returns undefined for absent, non-object, or array meta', () => {
+    expect(readMetaFromMeta(undefined)).toBeUndefined()
+    expect(readMetaFromMeta(null)).toBeUndefined()
+    expect(readMetaFromMeta('nope')).toBeUndefined()
+    expect(readMetaFromMeta([good])).toBeUndefined()
+  })
+
+  it('returns undefined when a field is missing or the wrong type (defensive narrowing)', () => {
+    expect(readMetaFromMeta({ ...good, path: 5 })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, offset: '1' })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, totalLines: '1' })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, lines: 'nope' })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, lines: [{ number: '1', text: 'x' }] })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, lines: [{ number: 1 }] })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, lines: [null] })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, lang: 5 })).toBeUndefined()
+  })
+
+  it('rejects an offset that is not a 1-based integer', () => {
+    expect(readMetaFromMeta({ ...good, offset: 0 })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, offset: 1.5 })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, offset: NaN })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, offset: Infinity })).toBeUndefined()
+  })
+
+  it('rejects a first line number below offset', () => {
+    expect(readMetaFromMeta({ ...good, offset: 2, lines: [{ number: 1, text: 'x' }], totalLines: 2 })).toBeUndefined()
+  })
+
+  it('rejects a line number that is not a 1-based integer', () => {
+    expect(readMetaFromMeta({ ...good, lines: [{ number: 0, text: 'x' }], totalLines: 1 })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, lines: [{ number: 1.5, text: 'x' }], totalLines: 2 })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, lines: [{ number: NaN, text: 'x' }], totalLines: 1 })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, lines: [{ number: Infinity, text: 'x' }], totalLines: 1 })).toBeUndefined()
+  })
+
+  it('rejects a totalLines that is not a non-negative integer', () => {
+    expect(readMetaFromMeta({ ...good, totalLines: -1 })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, totalLines: 1.5 })).toBeUndefined()
+    expect(readMetaFromMeta({ ...good, totalLines: NaN })).toBeUndefined()
+  })
+
+  it('rejects lines that do not strictly increase or exceed totalLines', () => {
+    const twoLines = { path: '/abs/a', offset: 1, lang: 'ts' }
+    // Duplicate line numbers.
+    expect(readMetaFromMeta({ ...twoLines, lines: [{ number: 1, text: 'a' }, { number: 1, text: 'b' }], totalLines: 2 })).toBeUndefined()
+    // Out-of-order line numbers.
+    expect(readMetaFromMeta({ ...twoLines, lines: [{ number: 2, text: 'b' }, { number: 1, text: 'a' }], totalLines: 2 })).toBeUndefined()
+    // A line number past totalLines.
+    expect(readMetaFromMeta({ ...twoLines, lines: [{ number: 3, text: 'c' }], totalLines: 2 })).toBeUndefined()
+  })
+})
--- a/packages/fs/tool-fs/tests/tools.spec.ts
+++ b/packages/fs/tool-fs/tests/tools.spec.ts
@@ -320,6 +320,39 @@ describe('read tool', () => {
    expect(text(result)).toContain('Output capped.')
  })

+  it('attaches the structured window as presentation meta, and presentResult narrows it into a read card', async () => {
+    const { ctx, fs } = await setup()
+    fs.files.set('key:a.ts', 'const x = 1\nconst y = 2')
+    const result = await call(ctx, 'read', { file_path: 'a.ts' })
+    expect(result.isError).toBe(false)
+    if (result.isError) throw new Error('expected read success')
+    // The extension drives the lang hint; the window rides on persisted meta.
+    expect(result.meta).toEqual({
+      path: '/abs/a.ts',
+      offset: 1,
+      lines: [{ number: 1, text: 'const x = 1' }, { number: 2, text: 'const y = 2' }],
+      totalLines: 2,
+      lang: 'ts',
+    })
+    const view = ctx.tools.get('read')?.presentResult?.({ file_path: 'a.ts' }, result)
+    expect(view).toEqual({
+      card: 'read',
+      path: '/abs/a.ts',
+      offset: 1,
+      lines: [{ number: 1, text: 'const x = 1' }, { number: 2, text: 'const y = 2' }],
+      totalLines: 2,
+      lang: 'ts',
+      content: [{ type: 'text', text: '1: const x = 1\n2: const y = 2\n\n(End of file - total 2 lines)' }],
+    })
+  })
+
+  it('omits the lang hint in meta for an extension that maps to no language', async () => {
+    const { ctx, fs } = await setup()
+    fs.files.set('key:notes', 'plain')
+    const result = await call(ctx, 'read', { file_path: 'notes' })
+    if (result.isError) throw new Error('expected read success')
+    expect(result.meta).toEqual({ path: '/abs/notes', offset: 1, lines: [{ number: 1, text: 'plain' }], totalLines: 1 })
+  })
 })

 describe('formatReadOutput footer variants', () => {
@@ -450,33 +483,72 @@ describe('tool-owned presentation (pure presentCall)', () => {
    })
  })

-  it('read: completed presentation removes the model-facing XML envelope', async () => {
-    expect(await presentResult('read', { file_path: 'a.txt' }, {
-      content: [{ type: 'text', text: '<path>/tmp/a.txt</path>\n<type>file</type>\n<content>\n1: hello\n\n(End of file - total 1 lines)\n</content>' }],
+  it('read: completed presentation is a read card carrying the structured window with the envelope stripped', async () => {
+    // The structured line data rides on persisted meta (the raw output object is
+    // not on the wire); presentResult narrows it and appends the stripped text as
+    // the no-capability `content` fallback.
+    const meta = { path: '/tmp/a.ts', offset: 1, lines: [{ number: 1, text: 'hello' }], totalLines: 1, lang: 'ts' }
+    expect(await presentResult('read', { file_path: 'a.ts' }, {
+      content: [{ type: 'text', text: '<path>/tmp/a.ts</path>\n<type>file</type>\n<content>\n1: hello\n\n(End of file - total 1 lines)\n</content>' }],
      isError: false,
+      meta,
    })).toEqual({
-      card: 'generic',
+      card: 'read',
+      path: '/tmp/a.ts',
+      offset: 1,
+      lines: [{ number: 1, text: 'hello' }],
+      totalLines: 1,
+      lang: 'ts',
      content: [{ type: 'text', text: '1: hello\n\n(End of file - total 1 lines)' }],
    })
-    expect(await presentResult('read', { file_path: 'a.txt' }, {
+    // A window whose extension maps to no language omits `lang` from the card.
+    expect(await presentResult('read', { file_path: 'notes' }, {
+      content: [{ type: 'text', text: '<path>/tmp/notes</path>\n<type>file</type>\n<content>\nbody\n</content>' }],
+      isError: false,
+      meta: { path: '/tmp/notes', offset: 1, lines: [{ number: 1, text: 'body' }], totalLines: 1 },
+    })).toEqual({
+      card: 'read',
+      path: '/tmp/notes',
+      offset: 1,
+      lines: [{ number: 1, text: 'body' }],
+      totalLines: 1,
+      content: [{ type: 'text', text: 'body' }],
+    })
+    // Malformed envelope text with valid meta still declines (the fallback text is unavailable).
+    expect(await presentResult('read', { file_path: 'a.ts' }, {
      content: [{ type: 'text', text: 'malformed replay' }],
      isError: false,
+      meta,
+    })).toBeUndefined()
+    // Valid envelope but absent/malformed meta declines to the generic fallback.
+    expect(await presentResult('read', { file_path: 'a.ts' }, {
+      content: [{ type: 'text', text: '<path>/tmp/a.ts</path>\n<type>file</type>\n<content>\n1: hello\n</content>' }],
+      isError: false,
+    })).toBeUndefined()
+    expect(await presentResult('read', { file_path: 'a.ts' }, {
+      content: [{ type: 'text', text: '<path>/tmp/a.ts</path>\n<type>file</type>\n<content>\n1: hello\n</content>' }],
+      isError: false,
+      meta: { path: '/tmp/a.ts', lines: 'nope', totalLines: 1 },
    })).toBeUndefined()
  })

  it('read: completed presentation declines errors and non-single-text content', async () => {
    const envelope = '<path>/tmp/a.txt</path>\n<type>file</type>\n<content>\nbody\n</content>'
+    const meta = { path: '/tmp/a.txt', offset: 1, lines: [{ number: 1, text: 'body' }], totalLines: 1 }
    expect(await presentResult('read', { file_path: 'a.txt' }, {
      content: [{ type: 'text', text: envelope }],
      isError: true,
+      meta,
    })).toBeUndefined()
    expect(await presentResult('read', { file_path: 'a.txt' }, {
      content: [{ type: 'text', text: envelope }, { type: 'text', text: 'second' }],
      isError: false,
+      meta,
    })).toBeUndefined()
    expect(await presentResult('read', { file_path: 'a.txt' }, {
      content: [{ type: 'reasoning', text: envelope }],
      isError: false,
+      meta,
    })).toBeUndefined()
  })

--- a/packages/host/apiproxy/README.i18n.yaml
+++ b/packages/host/apiproxy/README.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/host/apiproxy/README.md
-README.md: 5519298ad32554f87e45df08949e99d5117ba84a
-README.zh.md: c0970b6eb2bd05bad853a560e4b5c911efd5b32f
+README.md: 9b7cdc6ebff9214ffb4472f539c30a83e9107428
+README.zh.md: 814fa3c4ac4c8608e9be67c511b7a4a71a559777
--- a/packages/host/apiproxy/README.md
+++ b/packages/host/apiproxy/README.md
@@ -22,7 +22,7 @@ Session model routing is a session-domain contract. `session.models` returns the

 Pending queued input is a live control-plane contract, not session history. The gateway mirrors queued `InboxItem` occurrences from `agent/inbox/*` and broadcasts authoritative `session/queue` snapshots on every queued change and reconnect; pending steering stays outside this Web projection. `session.updateQueue` addresses one `InboxItemId`: edit replaces pending content and remove discards it. A driver claim wins races by retiring the address before admission; a later operation returns `queue-item-not-found`. The operation queries only an attached Agent and never resumes a cold session because process-local inbox identities do not survive restart or disposal. The client never infers retirement from turn or status events.

-Workspace and Session lists are separate reconnect baselines. `workspace.create` creates a unique name or adopts an existing directory, `workspace.delete` removes only the Workspace registration, `session.create` accepts an optional preallocated Session id, and `host/workspace-changed`, `host/workspace-removed`, plus `host/session-added` carry committed increments in either arrival order. Registration deletion preserves the directory and session logs; its Sessions remain in `session.list` and become Ungrouped. `SessionSummary.blank` and the `host/session-added` frame carry the derived zero-events bit: clients hide blank sessions and reuse them per workspace, flip blank on the first `host/session-status(running:true)`, and treat `session.list` as the reconnect authority; cold summaries are never blank because lazy persistence keeps never-appended sessions out of `list()`.
+Workspace and Session lists are separate reconnect baselines. `workspace.create` creates a unique name or adopts an existing directory, `workspace.delete` removes only the Workspace registration, `session.create` accepts an optional preallocated Session id, and `host/workspace-changed`, `host/workspace-removed`, plus `host/session-added` carry committed increments in either arrival order. `workspace.archiveSession` adds one session to the registry-global archive set and answers the full updated set; `workspace.list` carries that set as the reconnect baseline and `host/archived-sessions-changed` pushes the full snapshot after every durable change. Archiving hides the session from grouping surfaces without touching its log or its workspace account; a session neither live nor persisted fails with `session-not-found`. Registration deletion preserves the directory and session logs; its Sessions remain in `session.list` and become Ungrouped. `SessionSummary.blank` and the `host/session-added` frame carry the derived zero-events bit: clients hide blank sessions and reuse them per workspace, flip blank on the first `host/session-status(running:true)`, and treat `session.list` as the reconnect authority; cold summaries are never blank because lazy persistence keeps never-appended sessions out of `list()`.

 `session.search` is a bounded content-search projection over the sessions visible through `session.list`. The gateway asks the optional `ctx.sessionQuery` service for globally ranked current-surface user, assistant, and steering matches, consumes that stream until it has at most 20 visible session/snippet pairs plus one lookahead, and revalidates every hit against the list-derived authorization set before returning it. Provider pages start at 20 hits; when a first-page request rejects that limit, the gateway probes 10, 5, 2, then 1 and retains the learned size for continuation and stale-generation restarts. Returned snippets contain at most 240 Unicode code points, and the response schema independently enforces that bound at each client boundary. Keeping the authorization set in Host memory avoids SQLite's variable ceiling for large valid corpora without weakening visibility or ranking.

--- a/packages/host/apiproxy/README.zh.md
+++ b/packages/host/apiproxy/README.zh.md
@@ -22,7 +22,7 @@

 待处理的 queued 输入属于实时控制平面契约，而非会话历史。网关镜像来自 `agent/inbox/*` 的 queued `InboxItem` 入队项，并在每次 queued 变更和重连时广播权威的 `session/queue` 快照；待处理 steering（中途引导）不进入此 Web 投影。`session.updateQueue` 通过 `InboxItemId` 寻址单个项：编辑会替换待处理内容，移除会将其丢弃。驱动器在接纳前退役寻址标识，因此认领会赢得竞态；之后的操作返回 `queue-item-not-found`。该操作只查询当前已挂载的 Agent，绝不恢复冷会话，因为进程本地 inbox 标识无法在重启或资源释放后存活。客户端绝不根据轮次或状态事件推断项已退役。

-Workspace 列表与 Session 列表是相互独立的重连基线。`workspace.create` 会创建唯一名称或接纳现有目录，`workspace.delete` 只移除 Workspace 注册记录，`session.create` 接受可选的预分配 Session id，`host/workspace-changed`、`host/workspace-removed` 与 `host/session-added` 则以任意到达顺序携带已提交的增量。删除注册记录会保留目录和会话日志；相关 Session 仍留在 `session.list` 中，并进入 Ungrouped。`SessionSummary.blank` 与 `host/session-added` 帧携带派生的零事件位：客户端隐藏空白会话并按 workspace 复用它们，在首个 `host/session-status(running:true)` 时翻转 blank，并以 `session.list` 作为重连权威；冷会话摘要永远不是空白：惰性持久化让从未追加过事件的会话根本不出现在 `list()` 中。
+Workspace 列表与 Session 列表是相互独立的重连基线。`workspace.create` 会创建唯一名称或接纳现有目录，`workspace.delete` 只移除 Workspace 注册记录，`session.create` 接受可选的预分配 Session id，`host/workspace-changed`、`host/workspace-removed` 与 `host/session-added` 则以任意到达顺序携带已提交的增量。`workspace.archiveSession` 向注册表级全局归档集合添加一个会话，并应答完整的更新后集合；`workspace.list` 携带该集合作为重连基线，`host/archived-sessions-changed` 在每次持久变更后推送完整快照。归档只把会话从各分组视图中隐藏，不触碰其日志和 workspace 记账；既非实时也未持久化的会话以 `session-not-found` 失败。删除注册记录会保留目录和会话日志；相关 Session 仍留在 `session.list` 中，并进入 Ungrouped。`SessionSummary.blank` 与 `host/session-added` 帧携带派生的零事件位：客户端隐藏空白会话并按 workspace 复用它们，在首个 `host/session-status(running:true)` 时翻转 blank，并以 `session.list` 作为重连权威；冷会话摘要永远不是空白：惰性持久化让从未追加过事件的会话根本不出现在 `list()` 中。

 `session.search` 是以 `session.list` 所列会话为范围的有界内容搜索投影。网关向可选的 `ctx.sessionQuery` 服务请求全局排序后的当前 surface user、assistant 和 steering（中途引导）匹配项，并持续消费该结果流，直到获得至多 20 个可见会话／snippet 对及一个前瞻项；返回前仍会依据从列表推导的授权集合重新校验每个命中。提供方分页初始请求 20 个命中；如果第一页请求因这一上限被拒绝，网关会依次探测 10、5、2、1，并在续传和陈旧世代重启中沿用探测所得的页面大小。返回的 snippet 最多包含 240 个 Unicode 码点，响应 schema 则会在每个客户端边界独立强制执行该上限。将授权集合保留在宿主内存中，可在不削弱可见性或排序的前提下避开有效大型语料库的 SQLite 变量上限。

--- a/packages/host/apiproxy/src/api-proxy.ts
+++ b/packages/host/apiproxy/src/api-proxy.ts
@@ -21,7 +21,7 @@ import { SessionQueryError, type SessionSearchCursor } from '@deepseek-ai/dsh-se
 import type { Workspace, WorkspaceRecord } from '@deepseek-ai/dsh-workspace'
 import {
  workspaceDomainState, workspaceRecord, WorkspaceId as brandWorkspaceId,
-  WorkspaceMoveInvalidError, WorkspaceNameConflictError,
+  WorkspaceMoveInvalidError, WorkspaceNameConflictError, WorkspaceUnknownSessionError,
 } from '@deepseek-ai/dsh-workspace'
 // Type-only: brings the `ctx.tools` Context merge into this program (viewFor reads presenters).
 import type {} from '@deepseek-ai/dsh-tools'
@@ -1565,7 +1565,10 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro

    workspace: {
      list(request) {
-        return Promise.resolve(ok(request, { items: ctx.workspace.list().map(workspaceView) }))
+        return Promise.resolve(ok(request, {
+          items: ctx.workspace.list().map(workspaceView),
+          archivedSessionIds: [...ctx.workspace.archivedSessionIds],
+        }))
      },

      // Exactly one of path/name arrives (schema refine). Existing-folder
@@ -1681,6 +1684,23 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
        }
        return ok(request, { workspace: workspaceView(workspace) })
      },
+
+      async archiveSession(request) {
+        const { sessionId } = request.payload
+        try {
+          await ctx.workspace.archiveSession(sessionId)
+        } catch (error: unknown) {
+          // Only the registry's unknown-session rejection is the business
+          // code; storage/durability failures propagate as internal errors.
+          if (!(error instanceof WorkspaceUnknownSessionError)) throw error
+          return err(request, {
+            code: 'session-not-found',
+            message: error.message,
+            details: { sessionId },
+          })
+        }
+        return ok(request, { archivedSessionIds: [...ctx.workspace.archivedSessionIds] })
+      },
    },

    host: {
@@ -2092,6 +2112,10 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
        const committedWorkspaceIds = new Set(
          ctx.workspace.list().map(workspace => String(workspace.id)),
        )
+        // Frame-dedup baseline, same posture as committedWorkspaceIds: the
+        // stream opens against the current set; workspace.list re-baselines
+        // reconnecting clients, so only later changes need frames.
+        let archivedSessionIds = ctx.workspace.archivedSessionIds
        const disposers = [
          ctx.on('session/created', (session: Session) => {
            queue.push(frame({
@@ -2128,6 +2152,14 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
                committedWorkspaceIds.add(workspaceId)
                queue.push(frame({ type: 'host/workspace-changed', workspace: workspaceView(workspace) }))
              }
+              if (state.archivedSessionIds.length !== archivedSessionIds.length
+                || state.archivedSessionIds.some((id, index) => id !== archivedSessionIds[index])) {
+                archivedSessionIds = state.archivedSessionIds
+                queue.push(frame({
+                  type: 'host/archived-sessions-changed',
+                  archivedSessionIds: [...state.archivedSessionIds],
+                }))
+              }
              return
            }
            if (change.table !== 'workspaces') return
--- a/packages/host/apiproxy/src/api/events.schema.ts
+++ b/packages/host/apiproxy/src/api/events.schema.ts
@@ -71,6 +71,7 @@ export const hostFrameSchema = z.discriminatedUnion('type', [
  z.object({ type: z.literal('host/agent-error'), sessionId: sessionIdSchema, message: z.string() }),
  z.object({ type: z.literal('host/workspace-changed'), workspace: workspaceViewSchema }),
  z.object({ type: z.literal('host/workspace-removed'), workspaceId: workspaceIdSchema }),
+  z.object({ type: z.literal('host/archived-sessions-changed'), archivedSessionIds: z.array(sessionIdSchema) }),
  z.object({ type: z.literal('host/commands-changed') }),
  z.object({ type: z.literal('host/settings-changed'), ns: z.string() }),
  z.object({ type: z.literal('host/credentials-changed'), ref: z.string() }),
--- a/packages/host/apiproxy/src/api/events.ts
+++ b/packages/host/apiproxy/src/api/events.ts
@@ -101,7 +101,9 @@ export type MuxFrame =
 * workspace mutation (create/attach/order change — the client upserts, while
 * `workspace.list` provides the reconnect baseline); workspace-removed is the
 * committed registration-deletion increment and never implies directory or
- * session-log deletion.
+ * session-log deletion; archived-sessions-changed pushes the full registry
+ * archive set after every durable change (same full-snapshot posture as
+ * workspace-changed — `workspace.list` re-baselines it on reconnect).
 */
 export type HostFrame =
  | { type: 'host/session-added'; sessionId: SessionId; blank: boolean; parentSessionId?: SessionId; cwd?: string }
@@ -110,6 +112,7 @@ export type HostFrame =
  | { type: 'host/agent-error'; sessionId: SessionId; message: string }
  | { type: 'host/workspace-changed'; workspace: WorkspaceView }
  | { type: 'host/workspace-removed'; workspaceId: WorkspaceView['workspaceId'] }
+  | { type: 'host/archived-sessions-changed'; archivedSessionIds: SessionId[] }
  /**
   * The command registry changed (`commands/change` passthrough). Pure
   * invalidation signal, no payload: clients refetch `command.list` in the
--- a/packages/host/apiproxy/src/api/rpc-map.ts
+++ b/packages/host/apiproxy/src/api/rpc-map.ts
@@ -42,6 +42,7 @@ export interface RpcMethodMap {
  'workspace.rename': WorkspaceApi['rename']
  'workspace.delete': WorkspaceApi['delete']
  'workspace.insertSessionBefore': WorkspaceApi['insertSessionBefore']
+  'workspace.archiveSession': WorkspaceApi['archiveSession']
  'command.list': CommandsApi['list']
  'command.execute': CommandsApi['execute']
  'skill.list': SkillsApi['list']
--- a/packages/host/apiproxy/src/api/workspace.schema.ts
+++ b/packages/host/apiproxy/src/api/workspace.schema.ts
@@ -28,6 +28,7 @@ export const workspaceListRequestSchema = z.object({}) satisfies z.ZodType<Wire<
 /** workspace.list response value. */
 export const workspaceListValueSchema = z.object({
  items: z.array(workspaceViewSchema),
+  archivedSessionIds: z.array(sessionIdSchema),
 }) satisfies z.ZodType<Wire<ResponseValue<'workspace.list'>>>

 /** workspace.create request payload: exactly one of path/name (the contract's create spellings). */
@@ -80,3 +81,13 @@ export const workspaceInsertSessionBeforeRequestSchema = z.object({
 export const workspaceInsertSessionBeforeValueSchema = z.object({
  workspace: workspaceViewSchema,
 }) satisfies z.ZodType<Wire<ResponseValue<'workspace.insertSessionBefore'>>>
+
+/** workspace.archiveSession request payload. */
+export const workspaceArchiveSessionRequestSchema = z.object({
+  sessionId: sessionIdSchema,
+}) satisfies z.ZodType<Wire<RequestPayload<'workspace.archiveSession'>>>
+
+/** workspace.archiveSession response value: the full updated archive set. */
+export const workspaceArchiveSessionValueSchema = z.object({
+  archivedSessionIds: z.array(sessionIdSchema),
+}) satisfies z.ZodType<Wire<ResponseValue<'workspace.archiveSession'>>>
--- a/packages/host/apiproxy/src/api/workspace.ts
+++ b/packages/host/apiproxy/src/api/workspace.ts
@@ -37,8 +37,13 @@ export interface WorkspaceView {

 /** Workspace-domain unary methods (the map keys workspace.* of RpcMethodMap). */
 export interface WorkspaceApi {
-  /** Lists all workspaces in the registry's durable display order. */
-  list(request: RpcRequest<{}>): Promise<RpcResponse<{ items: WorkspaceView[] }>>
+  /**
+   * Lists all workspaces in the registry's durable display order, plus the
+   * registry-global archive set (the reconnect baseline of
+   * `host/archived-sessions-changed`). Archived sessions stay in their
+   * workspace's `sessionIds` account; grouping surfaces hide them.
+   */
+  list(request: RpcRequest<{}>): Promise<RpcResponse<{ items: WorkspaceView[]; archivedSessionIds: SessionId[] }>>

  /**
   * Creates (or idempotently resolves) a workspace. Exactly one of `path` /
@@ -86,4 +91,15 @@ export interface WorkspaceApi {
    sessionId: SessionId
    beforeSessionId?: SessionId
  }>): Promise<RpcResponse<{ workspace: WorkspaceView }>>
+
+  /**
+   * Adds one session to the registry-global archive set: the session
+   * disappears from every grouping surface but keeps its session log and its
+   * workspace accounting slot (a future unarchive restores its position).
+   * Idempotent for an already archived id. A session neither live nor in
+   * session persistence fails with `session-not-found`. Returns the full
+   * updated set (same snapshot the changed frame carries).
+   */
+  archiveSession(request: RpcRequest<{ sessionId: SessionId }>):
+  Promise<RpcResponse<{ archivedSessionIds: SessionId[] }>>
 }
--- a/packages/host/apiproxy/src/fetch/client.ts
+++ b/packages/host/apiproxy/src/fetch/client.ts
@@ -31,6 +31,7 @@ import {
  sessionUpdateQueueValueSchema,
 } from '../api/sessions.schema.ts'
 import {
+  workspaceArchiveSessionValueSchema,
  workspaceCreateValueSchema,
  workspaceDeleteValueSchema,
  workspaceInsertSessionBeforeValueSchema,
@@ -98,6 +99,7 @@ export interface IApiClient {
    rename(payload: RequestPayload<'workspace.rename'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.rename'>>>
    delete(payload: RequestPayload<'workspace.delete'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.delete'>>>
    insertSessionBefore(payload: RequestPayload<'workspace.insertSessionBefore'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.insertSessionBefore'>>>
+    archiveSession(payload: RequestPayload<'workspace.archiveSession'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.archiveSession'>>>
  }
  commands: {
    list(payload: RequestPayload<'command.list'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'command.list'>>>
@@ -163,6 +165,7 @@ const UNARY_VALUE_SCHEMAS: { [K in keyof RpcMethodMap]: z.ZodType<Wire<ResponseV
  'workspace.rename': workspaceRenameValueSchema,
  'workspace.delete': workspaceDeleteValueSchema,
  'workspace.insertSessionBefore': workspaceInsertSessionBeforeValueSchema,
+  'workspace.archiveSession': workspaceArchiveSessionValueSchema,
  'command.list': commandListValueSchema,
  'command.execute': commandExecuteValueSchema,
  'skill.list': skillListValueSchema,
@@ -400,6 +403,7 @@ export abstract class AbstractApiClient implements IApiClient {
    rename: (payload, signal) => this.callUnary('workspace.rename', payload, signal),
    delete: (payload, signal) => this.callUnary('workspace.delete', payload, signal),
    insertSessionBefore: (payload, signal) => this.callUnary('workspace.insertSessionBefore', payload, signal),
+    archiveSession: (payload, signal) => this.callUnary('workspace.archiveSession', payload, signal),
  }

  readonly commands: IApiClient['commands'] = {
--- a/packages/host/apiproxy/src/fetch/handler.ts
+++ b/packages/host/apiproxy/src/fetch/handler.ts
@@ -33,6 +33,7 @@ import {
  hostPickDirectoryRequestSchema,
 } from '../api/host.schema.ts'
 import {
+  workspaceArchiveSessionRequestSchema,
  workspaceCreateRequestSchema,
  workspaceDeleteRequestSchema,
  workspaceInsertSessionBeforeRequestSchema,
@@ -96,6 +97,7 @@ const UNARY_ROUTES: UnaryRoutes = {
  'workspace.rename': { schema: workspaceRenameRequestSchema, invoke: (api, r) => api.workspace.rename(r) },
  'workspace.delete': { schema: workspaceDeleteRequestSchema, invoke: (api, r) => api.workspace.delete(r) },
  'workspace.insertSessionBefore': { schema: workspaceInsertSessionBeforeRequestSchema, invoke: (api, r) => api.workspace.insertSessionBefore(r) },
+  'workspace.archiveSession': { schema: workspaceArchiveSessionRequestSchema, invoke: (api, r) => api.workspace.archiveSession(r) },
  'command.list': { schema: commandListRequestSchema, invoke: (api, r) => api.commands.list(r) },
  'command.execute': { schema: commandExecuteRequestSchema, invoke: (api, r, signal) => api.commands.execute(r, signal) },
  'skill.list': { schema: skillListRequestSchema, invoke: (api, r) => api.skills.list(r) },
--- a/packages/host/apiproxy/tests/api-proxy-workspace.spec.ts
+++ b/packages/host/apiproxy/tests/api-proxy-workspace.spec.ts
@@ -441,4 +441,44 @@ describe('Host Workspace increments', () => {
    expect(expectOk(await api.sessions.list(request({}))).items.map(item => item.sessionId)).toContain(sessionId)
    abort.abort()
  })
+
+  it('archives a session into the global set, keeps its accounting, and streams the set once', async () => {
+    const { api } = await harness()
+    const workspace = expectOk(await api.workspace.create(request({ name: 'archive-home' }))).workspace
+    const sessionId = SessionId('session-to-archive')
+    expectOk(await api.sessions.create(request({ workspaceId: workspace.workspaceId, sessionId })))
+    expect(expectOk(await api.workspace.list(request({}))).archivedSessionIds).toEqual([])
+
+    const abort = new AbortController()
+    const stream: AsyncIterator<RpcRequest<HostFrame>> =
+      api.events.host(request({}), abort.signal)[Symbol.asyncIterator]()
+    const changed = nextHostFrame(stream)
+    expect(expectOk(await api.workspace.archiveSession(request({ sessionId }))).archivedSessionIds)
+      .toEqual([sessionId])
+    expect(await changed).toMatchObject({
+      payload: { type: 'host/archived-sessions-changed', archivedSessionIds: [sessionId] },
+    })
+
+    // Accounting and the session itself are untouched; list re-baselines the set.
+    const listed = expectOk(await api.workspace.list(request({})))
+    expect(listed.archivedSessionIds).toEqual([sessionId])
+    expect(listed.items[0]?.sessionIds).toEqual([sessionId])
+    expect(expectOk(await api.sessions.list(request({}))).items.map(item => item.sessionId)).toContain(sessionId)
+
+    // The idempotent repeat emits no second frame: the next observed frame is
+    // the workspace-changed of a later attach, not another archive snapshot.
+    const after = nextHostFrame(stream)
+    expect(expectOk(await api.workspace.archiveSession(request({ sessionId }))).archivedSessionIds)
+      .toEqual([sessionId])
+    const otherSession = SessionId('session-after-archive')
+    expectOk(await api.sessions.create(request({ workspaceId: workspace.workspaceId, sessionId: otherSession })))
+    expect((await after).payload.type).not.toBe('host/archived-sessions-changed')
+
+    const missing = await api.workspace.archiveSession(request({ sessionId: SessionId('session-ghost') }))
+    expect(missing.result).toMatchObject({
+      ok: false,
+      error: { code: 'session-not-found', details: { sessionId: 'session-ghost' } },
+    })
+    abort.abort()
+  })
 })
--- a/packages/host/apiproxy/tests/client-handler.spec.ts
+++ b/packages/host/apiproxy/tests/client-handler.spec.ts
@@ -66,11 +66,12 @@ function scriptedApi(overrides: {
      ...overrides.host,
    },
    workspace: {
-      list: r => ok(r, { items: [] }),
+      list: r => ok(r, { items: [], archivedSessionIds: [] }),
      create: r => ok(r, { workspace: { workspaceId: 'w1' as never, path: '/t', title: 't', sessionIds: [], createdAt: '0', updatedAt: '0' }, created: true }),
      rename: r => ok(r, { workspace: { workspaceId: 'w1' as never, path: '/t', title: 't', sessionIds: [], createdAt: '0', updatedAt: '0' } }),
      delete: r => ok(r, { deleted: true as const }),
      insertSessionBefore: r => ok(r, { workspace: { workspaceId: 'w1' as never, path: '/t', title: 't', sessionIds: [], createdAt: '0', updatedAt: '0' } }),
+      archiveSession: r => ok(r, { archivedSessionIds: [r.payload.sessionId] }),
    },
    commands: {
      list: r => ok(r, { commands: [] }),
@@ -360,10 +361,12 @@ describe('workspace domain round trip', () => {
  it('routes both workspace methods through their handler rows and value schemas', async () => {
    const c = client(scriptedApi())
    const list = await c.workspace.list({})
-    expect(list.result).toEqual({ ok: true, value: { items: [] } })
+    expect(list.result).toEqual({ ok: true, value: { items: [], archivedSessionIds: [] } })
    const created = await c.workspace.create({ path: '/t' })
    expect(created.result.ok).toBe(true)
    if (created.result.ok) expect(created.result.value.created).toBe(true)
+    const archivedResponse = await c.workspace.archiveSession({ sessionId: 's-arch' as never })
+    expect(archivedResponse.result).toEqual({ ok: true, value: { archivedSessionIds: ['s-arch'] } })
  })

  it('rejects a create payload violating the exactly-one refine at the handler', async () => {
--- a/packages/host/apiproxy/tests/fetch-carrier.spec.ts
+++ b/packages/host/apiproxy/tests/fetch-carrier.spec.ts
@@ -122,7 +122,7 @@ function fakeApi(overrides: Partial<{ muxFrames: MuxFrame[]; hostFrames: HostFra
    },
    workspace: {
      async list(request) {
-        return { rpcId: request.rpcId, result: { ok: true, value: { items: [] } } }
+        return { rpcId: request.rpcId, result: { ok: true, value: { items: [], archivedSessionIds: [] } } }
      },
      async create(request) {
        return {
@@ -145,6 +145,9 @@ function fakeApi(overrides: Partial<{ muxFrames: MuxFrame[]; hostFrames: HostFra
          result: { ok: true, value: { workspace: { workspaceId: 'w1' as never, path: '/w', title: 'w', sessionIds: [], createdAt: 't', updatedAt: 't' } } },
        }
      },
+      async archiveSession(request) {
+        return { rpcId: request.rpcId, result: { ok: true, value: { archivedSessionIds: [request.payload.sessionId] } } }
+      },
    },
    commands: {
      async list(request) {
--- a/packages/host/apiproxy/tests/rpc-schemas.spec.ts
+++ b/packages/host/apiproxy/tests/rpc-schemas.spec.ts
@@ -20,6 +20,7 @@ import {
  hostListDirectoryRequestSchema, hostListDirectoryValueSchema,
 } from '../src/api/host.schema.ts'
 import {
+  workspaceArchiveSessionRequestSchema, workspaceArchiveSessionValueSchema,
  workspaceCreateRequestSchema, workspaceCreateValueSchema, workspaceIdSchema,
  workspaceDeleteRequestSchema, workspaceDeleteValueSchema,
  workspaceInsertSessionBeforeRequestSchema, workspaceInsertSessionBeforeValueSchema,
@@ -311,7 +312,16 @@ describe('workspace domain schemas', () => {
    expect(workspaceViewSchema.parse(view).sessionIds).toEqual(['s1'])
    expect(() => workspaceViewSchema.parse({ ...view, sessionIds: 's1' })).toThrow()
    expect(workspaceListRequestSchema.parse({})).toEqual({})
-    expect(workspaceListValueSchema.parse({ items: [view] }).items).toHaveLength(1)
+    expect(workspaceListValueSchema.parse({ items: [view], archivedSessionIds: ['s1'] }).items).toHaveLength(1)
+    expect(() => workspaceListValueSchema.parse({ items: [view] })).toThrow()
+  })
+
+  it('archiveSession request/value carry the id and the full updated set', () => {
+    expect(workspaceArchiveSessionRequestSchema.parse({ sessionId: 's1' }).sessionId).toBe('s1')
+    expect(() => workspaceArchiveSessionRequestSchema.parse({})).toThrow()
+    expect(workspaceArchiveSessionValueSchema.parse({ archivedSessionIds: ['s1', 's2'] }).archivedSessionIds)
+      .toEqual(['s1', 's2'])
+    expect(() => workspaceArchiveSessionValueSchema.parse({ archivedSessionIds: 's1' })).toThrow()
  })

  it('create requires exactly one of path/name (both refine arms)', () => {
--- a/packages/ui/tui/src/components/transcript.ts
+++ b/packages/ui/tui/src/components/transcript.ts
@@ -402,12 +402,15 @@ export class ToolCardComponent implements Component {
    const glyph = this.result === undefined ? '○' : '●'
    const rawBody = this.renderBody()
    const view = this.resultView ?? this.callView
-    // A generic card's own content, or a web card's fallback to the raw result
-    // content (the `web` view carries no `content` copy), both render as one dim
-    // Markdown block below, so links/lists/headings keep the unified dim styling
-    // rather than reading as bare text. Terminal and diff cards own their body
-    // styling, so they are excluded (mirrors renderBody's post-terminal/diff fallback).
-    const markdownContent = view.card === 'generic'
+    // A generic card's own content, or a read card's `content` fallback (the
+    // envelope-stripped file text — the TUI has no dedicated read rendering, so a
+    // read renders exactly as before the read card existed), or a web card's
+    // fallback to the raw result content (the `web` view carries no `content`
+    // copy), all render as one dim Markdown block below, so links/lists/headings
+    // keep the unified dim styling rather than reading as bare text. Terminal and
+    // diff cards own their body styling, so they are excluded (mirrors
+    // renderBody's post-terminal/diff fallback).
+    const markdownContent = view.card === 'generic' || view.card === 'read'
      ? view.content ?? this.result?.content
      : view.card === 'web'
        // A web resultView is only assigned alongside this.result (the result
@@ -532,11 +535,12 @@ export class ToolCardComponent implements Component {
      // rather than under the dim result-output color.
      return { prelude: [...hunks, footer], lines: [] }
    }
-    // The web card carries no `content` copy, so a `web` result view falls back
-    // to the raw result content here (`view.card === 'generic'` narrows the
-    // generic union arm; a `web` card takes the same fallback, mirroring the
-    // `markdownContent` selection in render()).
-    const content = (view.card === 'generic' ? view.content : undefined) ?? this.result?.content
+    // A generic or read card carries its own envelope-stripped `content`; a `web`
+    // card carries no `content` copy and falls back to the raw result content
+    // here. (Mirrors the `markdownContent` selection in render(); a read card has
+    // no dedicated TUI rendering, so its `content` takes the same body path,
+    // keeping read output as it was before the read card existed.)
+    const content = (view.card === 'generic' || view.card === 'read' ? view.content : undefined) ?? this.result?.content
    const prelude: string[] = []
    const lines: string[] = []
    // The presenter title headlines the body now that the header is a fixed
--- a/packages/workspace/workspace/README.i18n.yaml
+++ b/packages/workspace/workspace/README.i18n.yaml
@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/workspace/workspace/README.md
-README.md: bee3e4fcb5dded273f30942ee2e42ee93b839e62
-README.zh.md: 9a052f796fb7cc8756999bdc9b2ce905805730ab
+README.md: 11dc8172392e530ab4ea16f1b60473e5befb8089
+README.zh.md: 5c6e3cefe31759df27b8008861505527648ce3c4
--- a/packages/workspace/workspace/README.md
+++ b/packages/workspace/workspace/README.md
@@ -12,7 +12,7 @@ The entity/storage rationale lives in the [domain Agent Note](../../../.agents/n
 - `ctx.workspace.get(id)` / `list()` / `resolveByPath(path)` — cache-served lookups. `list()` is synchronous and follows durable registry order; `resolveByPath` is async because it applies the same `realpath` canon and rejects a missing path rather than creating it.
 - `ctx.workspace.delete(id)` — removes only the Workspace registration, its durable order entry, and its session account. Unknown ids return `false`; a removed record returns `true`. The directory, user files, live Sessions, and persisted session logs are never touched, so those Sessions become Ungrouped. A table-write failure restores the prior order and published entity.
 - `Workspace.attachSession(id)` — validates a live or persisted session header cwd against the workspace path and prepends a new id. Unknown sessions, absent/unresolvable/non-directory cwd values, and mismatches reject without writing. `detachSession` removes only the candidate index entry.
- `ctx.workspace.touchSession(id)` — moves only that validated, accounted session to the front. Ungrouped or filtered sessions are no-ops, and workspace order never changes.
+- `ctx.workspace.archiveSession(id)` / `archivedSessionIds` — the registry-global archive set, layered over workspace accounting: an archived session disappears from grouping surfaces but keeps its session log and its `sessionIds` slot, so a future unarchive restores its position. Archiving accepts any live or persisted session (accounted or Ungrouped), resolves without writing for an already archived id, and rejects an unknown id. State written before the field existed parses with an empty set.
 - `Workspace.sessionIds` — synchronous id-plus-canonical-cwd membership projection in durable candidate order. Missing headers, invalid cwd values, and mismatches are filtered; the next workspace mutation prunes them. A medium indexing one session under two workspaces, claiming one path from two records, or diverging from durable workspace order rejects at startup.
 - `Workspace.status()` — uncached directory check, `'ok' | 'missing-dir'`; a missing directory never mutates the record.

--- a/packages/workspace/workspace/README.zh.md
+++ b/packages/workspace/workspace/README.zh.md
@@ -12,7 +12,7 @@ DeepSeek Harness 的 Workspace 实体注册表（`ctx.workspace`）：通过领
 - `ctx.workspace.get(id)`/`list()`/`resolveByPath(path)`：由缓存提供的查找。`list()` 为同步操作，并遵循持久注册表顺序；`resolveByPath` 为异步操作，因为它采用相同的 `realpath` 规范化方式，并会拒绝缺失路径，而不是创建路径。
 - `ctx.workspace.delete(id)`：只移除 Workspace 注册记录、对应的持久顺序条目及会话归属记录。未知 id 返回 `false`，成功移除记录则返回 `true`。目录、用户文件、活跃会话和持久化会话日志绝不受影响，因此相关会话会进入 Ungrouped。表写入失败时会恢复原顺序和此前发布的实体。
 - `Workspace.attachSession(id)`：对照 workspace 路径验证实时或已持久化的会话头 cwd，并将新 id 前置。未知会话、缺失／无法解析／非目录的 cwd 值和不匹配情况都会在不写入的前提下被拒绝。`detachSession` 只移除候选索引条目。
- `ctx.workspace.touchSession(id)`：仅将已验证、已记账的会话移到最前。未分组或被过滤的会话不会触发任何操作，workspace 顺序绝不改变。
+- `ctx.workspace.archiveSession(id)`/`archivedSessionIds`：覆盖在 workspace 记账之上的注册表级全局归档集合：被归档的会话从各分组视图中消失，但其会话日志和 `sessionIds` 席位保持不变，未来取消归档时可恢复原位置。归档接受任何实时或已持久化的会话（无论已记账还是 Ungrouped），对已归档的 id 直接完成而不写入，并拒绝未知 id。在该字段出现之前写入的状态解析为一个空集合。
 - `Workspace.sessionIds`：按持久候选顺序提供同步 id 加规范 cwd 成员投影。缺失头部、无效 cwd 值和不匹配情况都被过滤；下一次 workspace 变更会剪除它们。如果同一存储介质将一个会话索引到两个 workspace 下、用两条记录声明同一路径，或偏离持久 workspace 顺序，启动会被拒绝。
 - `Workspace.status()`：未缓存的目录检查，返回 `'ok' | 'missing-dir'`；目录缺失绝不会改动记录。

--- a/packages/workspace/workspace/src/index.ts
+++ b/packages/workspace/workspace/src/index.ts
@@ -49,6 +49,20 @@ export class WorkspaceNameConflictError extends Error {
  }
 }

+/**
+ * An archiveSession request named a session neither live nor in session
+ * persistence — a definite miss only; storage faults propagate as themselves.
+ */
+export class WorkspaceUnknownSessionError extends Error {
+  /**
+   * @param sessionId - The unknown session id.
+   */
+  constructor(readonly sessionId: SessionId) {
+    super(`cannot archive session '${sessionId}': live sessions and session persistence hold no such session`)
+    this.name = 'WorkspaceUnknownSessionError'
+  }
+}
+

 declare module 'cordis' {
  interface Context {
@@ -181,6 +195,49 @@ export class WorkspaceRegistry extends Service {
    return this.enqueueOperation(() => this.deleteKnown(id))
  }

+  /**
+   * The registry-global archive set: sessions hidden from every grouping
+   * surface. Archiving never touches workspace accounting — an archived
+   * session keeps its `sessionIds` slot so unarchiving restores its position.
+   * @returns the archived session ids in archive order.
+   */
+  get archivedSessionIds(): readonly SessionId[] {
+    return this.requireState().archivedSessionIds
+  }
+
+  /**
+   * Archive one session durably. The session must exist (live or in session
+   * persistence); its workspace accounting — or lack of one — is irrelevant.
+   * An already archived id resolves without writing.
+   * @param sessionId - The session to archive.
+   * @returns resolution after durability.
+   */
+  archiveSession(sessionId: SessionId): Promise<void> {
+    return this.enqueueOperation(async () => {
+      // The chain slot serializes against every other registry write, so this
+      // check-then-write pair cannot interleave with another archive.
+      if (this.requireState().archivedSessionIds.includes(sessionId)) return
+      if (!(await this.sessionKnown(sessionId))) {
+        throw new WorkspaceUnknownSessionError(sessionId)
+      }
+      const state = this.requireState()
+      await this.setState({ ...state, archivedSessionIds: [...state.archivedSessionIds, sessionId] })
+    })
+  }
+
+  /**
+   * Whether a session is live, header-indexed, or present in a fresh
+   * persistence listing. Only a definite miss returns false — a failing
+   * `sessionPersistence.list()` propagates so storage faults never
+   * masquerade as an unknown session.
+   */
+  private async sessionKnown(id: SessionId): Promise<boolean> {
+    if (this.ctx.get('sessions')?.get(id) !== undefined) return true
+    if (this.headers.has(id)) return true
+    await this.indexHeaders(await this.ctx.sessionPersistence.list())
+    return this.headers.has(id)
+  }
+
  /**
   * Resolve by canonical directory path without creating or mutating a
   * workspace. A missing path rejects during `realpath`; an existing unowned
@@ -245,7 +302,11 @@ export class WorkspaceRegistry extends Service {
    }

    try {
-      await this.setState({ initialized: true, workspaceIds: [id, ...state.workspaceIds] })
+      await this.setState({
+        initialized: true,
+        workspaceIds: [id, ...state.workspaceIds],
+        archivedSessionIds: state.archivedSessionIds,
+      })
    } catch (error) {
      this.entities.delete(id)
      try {
@@ -276,6 +337,7 @@ export class WorkspaceRegistry extends Service {
    const nextState = {
      initialized: true,
      workspaceIds: state.workspaceIds.filter(workspaceId => workspaceId !== id),
+      archivedSessionIds: state.archivedSessionIds,
    }
    await this.setState({
      ...nextState,
@@ -329,7 +391,11 @@ export class WorkspaceRegistry extends Service {
      )
    }
    await this.requireTable().delete(pending.workspaceId)
-    await this.setState({ initialized: state.initialized, workspaceIds: state.workspaceIds })
+    await this.setState({
+      initialized: state.initialized,
+      workspaceIds: state.workspaceIds,
+      archivedSessionIds: state.archivedSessionIds,
+    })
  }

  private async bootstrap(headers: readonly SessionHeader[]): Promise<void> {
@@ -411,9 +477,9 @@ export class WorkspaceRegistry extends Service {
      .map(([id]) => id)

    if (!sameIds(state.workspaceIds, workspaceIds)) {
-      await this.setState({ initialized: false, workspaceIds })
+      await this.setState({ initialized: false, workspaceIds, archivedSessionIds: state.archivedSessionIds })
    }
-    await this.setState({ initialized: true, workspaceIds })
+    await this.setState({ initialized: true, workspaceIds, archivedSessionIds: state.archivedSessionIds })
  }

  private validateStoredState(state: WorkspaceDomainState): void {
--- a/packages/workspace/workspace/src/spec.ts
+++ b/packages/workspace/workspace/src/spec.ts
@@ -42,11 +42,16 @@ const workspacePendingMutation = z.discriminatedUnion('operation', [
 /**
 * Durable registry state. `initialized` distinguishes a valid empty registry
 * from one that still needs the header-only history bootstrap;
- * `workspaceIds` is the authoritative display order.
+ * `workspaceIds` is the authoritative display order. `archivedSessionIds` is
+ * the registry-global archive set layered over workspace accounting: an
+ * archived session keeps its `sessionIds` slot (unarchiving must restore the
+ * position), so the set never participates in the one-owner accounting
+ * invariant. Defaulted so records written before the field parse unchanged.
 */
 export const workspaceDomainState = z.object({
  initialized: z.boolean(),
  workspaceIds: z.array(workspaceId),
+  archivedSessionIds: z.array(z.string().transform(SessionId)).default([]),
  pendingMutation: workspacePendingMutation.optional(),
 })

@@ -64,7 +69,7 @@ export const workspaceDomainSpec = defineDomain({
  version: 2,
  global: {
    schema: workspaceDomainState,
-    initial: { initialized: false, workspaceIds: [] },
+    initial: { initialized: false, workspaceIds: [], archivedSessionIds: [] },
  },
  tables: { workspaces: domainTable<WorkspaceId, WorkspaceRecord>(workspaceRecord) },
 })
--- a/packages/workspace/workspace/tests/workspace.spec.ts
+++ b/packages/workspace/workspace/tests/workspace.spec.ts
@@ -135,9 +135,16 @@ function record(path: string, sessionIds: string[], createdAt = '2026-07-24T00:0
  }
 }

+/**
+ * Media written before archivedSessionIds existed omit the field; keeping the
+ * fixtures in that shape continuously proves the schema default upgrades them.
+ */
+type StoredDomainState = Omit<WorkspaceDomainState, 'archivedSessionIds'>
+  & Partial<Pick<WorkspaceDomainState, 'archivedSessionIds'>>
+
 function storedPool(
  entries: Array<[string, WorkspaceRecord]>,
-  state: WorkspaceDomainState,
+  state: StoredDomainState,
 ): MemoryMediaPool {
  const pool = new MemoryMediaPool()
  pool.versions.set('workspace', DOMAIN_VERSION)
@@ -185,7 +192,7 @@ describe('WorkspaceRegistry lifecycle and bootstrap', () => {
    await fiber.await()
    expect(ctx.workspace.list()).toEqual([])
    expect(list).toHaveBeenCalledTimes(1)
-    expect(storedState(pool)).toEqual({ initialized: true, workspaceIds: [] })
+    expect(storedState(pool)).toEqual({ initialized: true, workspaceIds: [], archivedSessionIds: [] })
  })

  it('bootstraps once from list headers only, in workspace/session createdAt order', async () => {
@@ -218,6 +225,7 @@ describe('WorkspaceRegistry lifecycle and bootstrap', () => {
    expect(storedState(result.pool)).toEqual({
      initialized: true,
      workspaceIds: result.registry.list().map(workspace => workspace.id),
+      archivedSessionIds: [],
    })
  })

@@ -246,7 +254,7 @@ describe('WorkspaceRegistry lifecycle and bootstrap', () => {
    const second = await harness({ pool, sessions: [header('late', late, 100)] })
    expect(second.list).not.toHaveBeenCalled()
    expect(second.registry.list()).toEqual([])
-    expect(storedState(pool)).toEqual({ initialized: true, workspaceIds: [] })
+    expect(storedState(pool)).toEqual({ initialized: true, workspaceIds: [], archivedSessionIds: [] })
  })

  it('reuses partial records after a bootstrap record write fails', async () => {
@@ -476,7 +484,7 @@ describe('WorkspaceRegistry create and lookup', () => {
    await expect(result.registry.delete(workspace.id)).resolves.toBe(false)
    expect(result.registry.get(workspace.id)).toBeUndefined()
    expect(result.registry.list()).toEqual([])
-    expect(storedState(result.pool)).toEqual({ initialized: true, workspaceIds: [] })
+    expect(storedState(result.pool)).toEqual({ initialized: true, workspaceIds: [], archivedSessionIds: [] })
    expect(result.pool.media.get('workspace')!.tables.get('workspaces')!.has(workspace.id)).toBe(false)
    await expect(realpath(dir)).resolves.toBe(dir)
    expect(result.list).toHaveBeenCalledTimes(1)
@@ -519,6 +527,7 @@ describe('WorkspaceRegistry create and lookup', () => {
    expect(storedState(pool)).toEqual({
      initialized: true,
      workspaceIds: [],
+      archivedSessionIds: [],
      pendingMutation: { operation: 'delete', workspaceId: workspace.id },
    })
    const reregistered = await first.registry.create(dir)
@@ -526,6 +535,7 @@ describe('WorkspaceRegistry create and lookup', () => {
    expect(storedState(pool)).toEqual({
      initialized: true,
      workspaceIds: [reregistered.id],
+      archivedSessionIds: [],
    })
    await first.fiber.dispose()

@@ -762,7 +772,7 @@ describe('header-validated membership projection', () => {
    const createRecovery = await harness({ pool: interruptedCreate })
    expect(createRecovery.registry.list()).toEqual([])
    expect(interruptedCreate.media.get('workspace')!.tables.get('workspaces')!.has(createId)).toBe(false)
-    expect(storedState(interruptedCreate)).toEqual({ initialized: true, workspaceIds: [] })
+    expect(storedState(interruptedCreate)).toEqual({ initialized: true, workspaceIds: [], archivedSessionIds: [] })

    const interruptedDelete = storedPool(
      [[deleteId, record(deleteDir, [])]],
@@ -775,7 +785,7 @@ describe('header-validated membership projection', () => {
    const deleteRecovery = await harness({ pool: interruptedDelete })
    expect(deleteRecovery.registry.list()).toEqual([])
    expect(interruptedDelete.media.get('workspace')!.tables.get('workspaces')!.has(deleteId)).toBe(false)
-    expect(storedState(interruptedDelete)).toEqual({ initialized: true, workspaceIds: [] })
+    expect(storedState(interruptedDelete)).toEqual({ initialized: true, workspaceIds: [], archivedSessionIds: [] })

    const corruptPending = storedPool(
      [[deleteId, record(deleteDir, [])]],
@@ -816,3 +826,74 @@ describe('workspace mutation and status', () => {
    expect(registry.get(workspace.id)).toBe(workspace)
  })
 })
+
+describe('registry-global session archive', () => {
+  it('archives durably in order, idempotently skips repeats, and leaves accounting untouched', async () => {
+    const dir = await makeDir('archive-home')
+    const result = await harness({ sessions: [header('kept', dir, 100), header('gone', dir, 200)] })
+    const workspace = result.registry.list()[0]!
+    expect(result.registry.archivedSessionIds).toEqual([])
+
+    await result.registry.archiveSession(SessionId('gone'))
+    expect(result.registry.archivedSessionIds).toEqual(['gone'])
+    // Archiving is a display-set write: the workspace account keeps the id.
+    expect(workspace.sessionIds).toContain('gone')
+    expect(storedState(result.pool).archivedSessionIds).toEqual(['gone'])
+    const changesAfterFirst = result.changes.filter(change => change.table === '').length
+
+    await result.registry.archiveSession(SessionId('gone'))
+    expect(result.registry.archivedSessionIds).toEqual(['gone'])
+    // The idempotent repeat neither rewrites the medium nor emits a change.
+    expect(result.changes.filter(change => change.table === '').length).toBe(changesAfterFirst)
+
+    await result.registry.archiveSession(SessionId('kept'))
+    expect(result.registry.archivedSessionIds).toEqual(['gone', 'kept'])
+  })
+
+  it('accepts unaccounted and live sessions but rejects unknown ids without writing', async () => {
+    const dir = await makeDir('archive-strays')
+    const live = await makeDir('archive-live')
+    const result = await harness({
+      sessions: [header('stray', dir, 100)],
+      liveSessions: [header('live-only', live, 200)],
+    })
+    await result.registry.archiveSession(SessionId('stray'))
+    await result.registry.archiveSession(SessionId('live-only'))
+    expect(result.registry.archivedSessionIds).toEqual(['stray', 'live-only'])
+
+    await expect(result.registry.archiveSession(SessionId('ghost')))
+      .rejects.toThrow(/cannot archive session 'ghost'/)
+    expect(storedState(result.pool).archivedSessionIds).toEqual(['stray', 'live-only'])
+  })
+
+  it('propagates a persistence-listing failure instead of reporting an unknown session', async () => {
+    const result = await harness({ sessions: [] })
+    result.list.mockRejectedValueOnce(new Error('persistence backend down'))
+    // The storage fault is the error — never WorkspaceUnknownSessionError,
+    // which the API layer would misreport as session-not-found.
+    await expect(result.registry.archiveSession(SessionId('unlisted')))
+      .rejects.toThrow(/persistence backend down/)
+    expect(storedState(result.pool).archivedSessionIds).toEqual([])
+  })
+
+  it('restores the archive set across restarts and defaults it for pre-field media', async () => {
+    const dir = await makeDir('archive-restart')
+    const pool = new MemoryMediaPool()
+    const first = await harness({ pool, sessions: [header('s1', dir, 100)] })
+    await first.registry.archiveSession(SessionId('s1'))
+    await first.fiber.dispose()
+
+    const second = await harness({ pool, sessions: [header('s1', dir, 100)] })
+    expect(second.registry.archivedSessionIds).toEqual(['s1'])
+    await second.fiber.dispose()
+
+    // A medium written before the field existed parses through the schema default.
+    const legacyId = WorkspaceId('00000000-0000-4000-8000-00000000000a')
+    const legacy = storedPool(
+      [[legacyId, record(dir, [])]],
+      { initialized: true, workspaceIds: [legacyId] },
+    )
+    const upgraded = await harness({ pool: legacy })
+    expect(upgraded.registry.archivedSessionIds).toEqual([])
+  })
+})