refactor(web): project usage and snapshot request context

2026-07-29 15:27:59 +08:00
parent e37cb23336
commit bf618dabf9
78 changed files with 748 additions and 934 deletions
--- a/packages/client/connection/src/client/api.ts
+++ b/packages/client/connection/src/client/api.ts
@@ -12,7 +12,7 @@ export type {
  WorkspaceApi, WorkspaceId, WorkspaceView,
  CommandsApi, CommandDescriptor, SkillsApi, SkillEntry,
  ModelCatalogFailure, ModelCatalogModel, ModelProviderGroup, ModelReasoning,
-  ModelReasoningEffort, ModelTarget, SessionMetrics, SessionModels, SessionProjectionsBlock,
+  ModelReasoningEffort, ModelRequestTelemetry, ModelTarget, SessionModels, SessionProjectionsBlock,
  GoalsApi, GoalRef,
 } from '@deepseek-ai/dsh-host-apiproxy/api'
 export type { ToolCallView, ToolResultView } from '@deepseek-ai/dsh-tools/presentation'
--- a/packages/client/connection/src/client/fixture.ts
+++ b/packages/client/connection/src/client/fixture.ts
@@ -15,6 +15,7 @@ import type {
  AssistantMessage,
  ContentBlock,
  MessageSource,
+  TokenUsage,
  ToolResultMessage,
  UserMessage,
 } from '@deepseek-ai/dsh-llm'
@@ -103,6 +104,16 @@ function sid(id: string): SessionId {
  return id as SessionId
 }

+/** Deterministic provider billing attached to fixture assistant messages. */
+function fixtureUsage(turn: number, step: number): TokenUsage {
+  return {
+    inputTokens: 20 + turn % 5,
+    outputTokens: 8 + step,
+    cacheReadTokens: turn === 0 ? 0 : 80,
+    cacheWriteTokens: turn % 10 === 0 ? 4 : 0,
+  }
+}
+
 /** fx-alpha history script: 60 turns (~130+ messages -> 3 pages at PAGE_MESSAGES=50),
 *  mixing reasoning blocks / tool call+result / steering / context. */
 function buildAlphaLog(): SessionEvent[] {
@@ -110,7 +121,17 @@ function buildAlphaLog(): SessionEvent[] {
  let time = Date.now() - 3_600_000
  const push = (e: Record<string, unknown>): number => {
    const seq = events.length
-    events.push({ seq, time: (time += 800), ...e })
+    const data = e['data'] as Record<string, unknown> | undefined
+    const authored = e['type'] === 'assistant/message' && data !== undefined
+      ? {
+        ...e,
+        data: {
+          ...data,
+          usage: fixtureUsage(data['turn'] as number, data['step'] as number),
+        },
+      }
+      : e
+    events.push({ seq, time: (time += 800), ...authored })
    return seq
  }
  for (let turn = 0; turn < 60; turn++) {
@@ -369,6 +390,60 @@ function permissionSelectOf(
  }
 }

+interface FixtureTokenUsageProjection {
+  uncachedInputTokens: number
+  outputTokens: number
+  cacheReadTokens: number
+  cacheWriteTokens: number
+}
+
+/** Fixture parallel of token-meter's last-sample-replacing usage projection. */
+function tokenUsageOf(log: readonly SessionEvent[]): FixtureTokenUsageProjection {
+  const totals: FixtureTokenUsageProjection = {
+    uncachedInputTokens: 0,
+    outputTokens: 0,
+    cacheReadTokens: 0,
+    cacheWriteTokens: 0,
+  }
+  let last: {
+    turn: number
+    step: number
+    buckets: FixtureTokenUsageProjection
+  } | null = null
+  for (const event of log) {
+    const item = event as unknown as {
+      type: string
+      data: {
+        turn?: number
+        step?: number
+        usage?: TokenUsage
+        chunk?: { type?: string; usage?: TokenUsage }
+      }
+    }
+    const usage = item.type === 'assistant/chunk' && item.data.chunk?.type === 'usage'
+      ? item.data.chunk.usage
+      : item.type === 'assistant/message'
+        ? item.data.usage
+        : undefined
+    if (usage === undefined || item.data.turn === undefined || item.data.step === undefined) continue
+    const buckets: FixtureTokenUsageProjection = {
+      uncachedInputTokens: usage.inputTokens,
+      outputTokens: usage.outputTokens,
+      cacheReadTokens: usage.cacheReadTokens ?? 0,
+      cacheWriteTokens: usage.cacheWriteTokens ?? 0,
+    }
+    const previous = last?.turn === item.data.turn && last.step === item.data.step
+      ? last.buckets
+      : undefined
+    totals.uncachedInputTokens += buckets.uncachedInputTokens - (previous?.uncachedInputTokens ?? 0)
+    totals.outputTokens += buckets.outputTokens - (previous?.outputTokens ?? 0)
+    totals.cacheReadTokens += buckets.cacheReadTokens - (previous?.cacheReadTokens ?? 0)
+    totals.cacheWriteTokens += buckets.cacheWriteTokens - (previous?.cacheWriteTokens ?? 0)
+    last = { turn: item.data.turn, step: item.data.step, buckets }
+  }
+  return totals
+}
+
 function projectionValuesOf(log: readonly SessionEvent[]): Record<string, unknown> {
  const values: Record<string, unknown> = {}
  const titleEvent = log.findLast(item => (item as { type: string }).type === 'session/title')
@@ -383,12 +458,28 @@ function projectionValuesOf(log: readonly SessionEvent[]): Record<string, unknow
  values['plan'] = planViewOf(log)
  // Always present (GoalService unit composed): null before create / after clear.
  values['goal'] = backscanGoal(log)
+  // Always present (token-meter composed): full-log provider billing.
+  values['tokenUsage'] = tokenUsageOf(log)
  return values
 }

 /** Host push-frame parallel: emit one session/projection frame per key the given event advanced. */
 function projectionFramesOf(id: SessionId, log: readonly SessionEvent[], event: SessionEvent): Extract<MuxFrame, { type: 'session/projection' }>[] {
  const type = (event as { type: string }).type
+  if (
+    (type === 'assistant/chunk'
+      && (event as unknown as { data: { chunk?: { type?: string } } }).data.chunk?.type === 'usage')
+    || (type === 'assistant/message'
+      && (event as unknown as { data: { usage?: TokenUsage } }).data.usage !== undefined)
+  ) {
+    return [{
+      type: 'session/projection',
+      sessionId: id,
+      key: 'tokenUsage',
+      value: tokenUsageOf(log),
+      seq: event.seq,
+    }]
+  }
  if (type === 'session/title') {
    const values = projectionValuesOf(log)
    /* v8 ignore next -- the advancing title event is in the log, so the key is present. */
@@ -853,7 +944,16 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
      replays.delete(id)
      const done = pieces.slice(0, i).join('')
      append(id, { type: 'assistant/chunk', data: { turn, step, chunk: { type: 'block-end', index: 0, block: { type: 'text', text: done } } } })
-      append(id, { type: 'assistant/message', surfaceOp: 'append', data: { turn, step, message: assistantMessage(text(aborted ? `${done}（已中断）` : done)) } })
+      append(id, {
+        type: 'assistant/message',
+        surfaceOp: 'append',
+        data: {
+          turn,
+          step,
+          message: assistantMessage(text(aborted ? `${done}（已中断）` : done)),
+          usage: fixtureUsage(turn, step),
+        },
+      })
      append(id, { type: 'step/end', data: { turn, step } })
      append(id, { type: 'turn/end', data: { turn, reason: { kind: aborted ? 'cancelled' : 'completed' } } })
      setRunning(id, false)
@@ -1036,6 +1136,19 @@ export function createFixtureApi(options: FixtureOptions = {}): ApiProxy {
          append(id, { type: 'plan/mode', data: { active: plan.wanted } })
        }
        append(id, { type: 'user/message', surfaceOp: 'append', data: userMessage(content) })
+        const target = modelTargets.get(id) ?? { provider: 'deepseek', model: 'deepseek-v4-flash' }
+        const usage = tokenUsageOf(logOf(id))
+        emitMux({
+          type: 'session/model-request',
+          sessionId: id,
+          turn,
+          step: 0,
+          provider: target.provider,
+          model: target.model,
+          contextTokens: usage.uncachedInputTokens + usage.outputTokens
+            + usage.cacheReadTokens + usage.cacheWriteTokens,
+          contextWindow: 128_000,
+        })
        startReply(
          id,
          turn,
--- a/packages/client/connection/src/client/index.ts
+++ b/packages/client/connection/src/client/index.ts
@@ -17,7 +17,7 @@ export type {
  ToolCallView, ToolResultView, WorkspaceApi, WorkspaceId, WorkspaceView,
  CommandsApi, CommandDescriptor, SkillsApi, SkillEntry,
  ModelCatalogFailure, ModelCatalogModel, ModelProviderGroup, ModelReasoning,
-  ModelReasoningEffort, ModelTarget, SessionMetrics, SessionModels, SessionProjectionsBlock,
+  ModelReasoningEffort, ModelRequestTelemetry, ModelTarget, SessionModels, SessionProjectionsBlock,
  RpcRequest, RpcResponse, RpcResult, RpcError, RpcErrorCode,
  ClientRequest, ServerResponse, ServerRequest, ClientResponse, RpcMessage, RpcReceipt,
  IApiClient, SessionId, SessionEvent, ContentBlock, StreamChunk,
--- a/packages/client/connection/tests/fixture.spec.ts
+++ b/packages/client/connection/tests/fixture.spec.ts
@@ -84,6 +84,12 @@ describe('createFixtureApi', () => {
        },
        plan: { active: false, pending: false },
        goal: null,
+        tokenUsage: {
+          uncachedInputTokens: 0,
+          outputTokens: 0,
+          cacheReadTokens: 0,
+          cacheWriteTokens: 0,
+        },
      } },
    })
  })
@@ -188,6 +194,20 @@ describe('createFixtureApi', () => {
    expect(types).toContain('assistant/chunk')
    expect(types).toContain('assistant/message')
    expect(types.at(-1)).toBe('turn/end')
+    expect(frames).toContainEqual({
+      type: 'session/model-request',
+      sessionId: id,
+      turn: 0,
+      step: 0,
+      provider: 'deepseek',
+      model: 'deepseek-v4-flash',
+      contextTokens: 0,
+      contextWindow: 128_000,
+    })
+    expect(frames.some(frame =>
+      frame.type === 'session/projection'
+      && frame.key === 'tokenUsage'
+      && (frame.value as { outputTokens?: number }).outputTokens === 8)).toBe(true)
    const finalize = frames.find((f): f is Extract<MuxFrame, { type: 'session/event' }> => f.type === 'session/event' && f.event.type === 'assistant/message')
    expect(JSON.stringify(finalize?.event.data)).toContain('（已中断）')
    // Idle cancel: no replay in flight, must not explode; running flips false.
@@ -219,7 +239,7 @@ describe('createFixtureApi', () => {
      const envelopes: RpcRequest<MuxFrame>[] = []
      for await (const envelope of api.events.mux(req({}), abort.signal)) {
        envelopes.push(envelope)
-        if (envelopes.length >= 8) abort.abort()
+        if (envelopes.length >= 9) abort.abort()
      }
      return envelopes
    }
@@ -227,16 +247,18 @@ describe('createFixtureApi', () => {
    const second = await openOnce()
    expect(first[0]?.payload).toMatchObject({ type: 'session/subscribed', sessionId: 'fx-alpha' })
    expect((first[0]?.payload as { lastSeq: number }).lastSeq).toBeGreaterThan(0)
-    // Projection baseline frames follow the subscribed frame (title + todos + permissions + plan + goal units).
+    // Projection baseline frames follow subscribed (domain units + token usage).
    expect(first[1]?.payload).toMatchObject({ type: 'session/projection', sessionId: 'fx-alpha', key: 'title', value: 'Fixture 历史会话' })
    expect(first[2]?.payload).toMatchObject({ type: 'session/projection', sessionId: 'fx-alpha', key: 'todos' })
    expect(first[3]?.payload).toMatchObject({ type: 'session/projection', sessionId: 'fx-alpha', key: 'permissions' })
    expect(first[4]?.payload).toMatchObject({ type: 'session/projection', sessionId: 'fx-alpha', key: 'plan', value: { active: false, pending: false } })
    expect(first[5]?.payload).toMatchObject({ type: 'session/projection', sessionId: 'fx-alpha', key: 'goal', value: null })
-    expect(first[6]?.payload).toMatchObject({ type: 'approval/requested', toolName: 'dangerous_tool' })
-    expect(second[6]?.rpcId).toBe(first[6]?.rpcId) // stable rpcId across replays (host replay semantics)
-    expect(first[7]?.payload).toMatchObject({ type: 'question/requested', sessionId: 'fx-alpha' })
-    expect(second[7]?.rpcId).toBe(first[7]?.rpcId)
+    expect(first[6]?.payload).toMatchObject({ type: 'session/projection', sessionId: 'fx-alpha', key: 'tokenUsage' })
+    expect(first[7]?.payload).toMatchObject({ type: 'approval/requested', toolName: 'dangerous_tool' })
+    expect(second[7]?.rpcId).toBe(first[7]?.rpcId) // stable rpcId across replays (host replay semantics)
+    expect(first[8]?.payload).toMatchObject({ type: 'question/requested', sessionId: 'fx-alpha' })
+    expect(second[8]?.rpcId).toBe(first[8]?.rpcId)
+    expect(first.some(envelope => envelope.payload.type === 'session/model-request')).toBe(false)
  })

  it('steer with no replay in flight falls through to a fresh queued turn; non-text blocks stringify empty', async () => {
--- 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: 879730733f3d89c3962d8c54bcfd53795a980049
-README.zh.md: 1b1d7f03d1f5f03c054dfeaa790a9f6f91e0dca2
+README.md: ba9a7d455e8a193f23884411eb1928a10f21ddd0
+README.zh.md: 873fefca48585efed010589917f2c63653b08e5b
--- a/packages/client/runtime/README.md
+++ b/packages/client/runtime/README.md
@@ -2,7 +2,7 @@

 English | [中文](README.zh.md)

-Client cordis boot and React-free object services: SlotsService wraps SlotCore and supplies renderer data sources; SessionsService owns Session objects, list/scope/history state; WorkspacesService depends on SessionsService and owns Workspace objects, list/actions, default-target derivation, and the New Session blank-reuse entry (`connectWorkspace`). The runtime fans the shared Host stream into both managers. Client sessions are always Host-born (Session+Agent+cwd in one `session.create`); the client holds no pre-entity session state — a session's Agent scope (the client mirror of host dsh-scope, keyed by the shared agent/session id) is born when its row enters the list mirror and dies with the prune. Contract: api-contracts v3 §4. Each `Session` holds a generic `ProjectionValueStore` seeded from the history-tail `projections` block and updated by `session/projection` frames under higher-seq-wins; domain keys (including `todos` and `title`) are read via `projections.faceOf` / `useProjection`, not via `ConversationSnapshot`. Durable `ConversationSnapshot.metrics` instead comes from the separate history-tail value and live `session/metrics` frames because point-in-time token-meter pressure can advance at the same durable log revision; only nondecreasing log and projection revisions are accepted. `ConversationSnapshot.modelRequestContextWindow` separately retains capacity from the latest `session/model-request` observed on the current mux connection. A later request replaces or clears that value, while `session/subscribed` clears both metrics ordering and capacity; reconnect, restore, and a new subscription therefore show no percentage until another request is observed. Missing metrics remain `null` rather than being inferred from the visible node window.
+Client cordis boot and React-free object services: SlotsService wraps SlotCore and supplies renderer data sources; SessionsService owns Session objects, list/scope/history state; WorkspacesService depends on SessionsService and owns Workspace objects, list/actions, default-target derivation, and the New Session blank-reuse entry (`connectWorkspace`). The runtime fans the shared Host stream into both managers. Client sessions are always Host-born (Session+Agent+cwd in one `session.create`); the client holds no pre-entity session state — a session's Agent scope (the client mirror of host dsh-scope, keyed by the shared agent/session id) is born when its row enters the list mirror and dies with the prune. Contract: api-contracts v3 §4. Each `Session` holds a generic `ProjectionValueStore` seeded from the history-tail `projections` block and updated by `session/projection` frames under higher-seq-wins; domain keys (including `todos`, `title`, and `tokenUsage`) are read via `projections.faceOf` / `useProjection`, not via `ConversationSnapshot`. `ConversationSnapshot.modelRequest` separately retains the complete latest `session/model-request` observed on the current mux connection. Each frame replaces the whole snapshot, so omitted numerator or capacity fields clear an earlier value. `SessionManager` buffers one pre-instantiation snapshot, while `session/subscribed`, disconnect, and removal clear resident and pending values; reconnect, restore, and a new subscription therefore show no context percentage until another request is observed. Model selection alone does not alter request telemetry.

 ## Workspace and Session lists

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

 [English](README.md) | 中文

-客户端 cordis 启动与不依赖 React 的对象服务：SlotsService 包装 SlotCore 并提供 renderer 数据源；SessionsService 拥有 Session 对象、列表／scope／history 状态；WorkspacesService 依赖 SessionsService，拥有 Workspace 对象、列表／操作、默认目标派生，以及 New Session 空会话复用入口（`connectWorkspace`）。运行时把共享 Host 流分发给两个 manager。客户端 Session 一律由 Host 出生（一次 `session.create` 同瞬产出 Session+Agent+cwd）；客户端不持有任何实体化之前的会话状态——Agent scope（host dsh-scope 的客户端镜像，以 agent/session 共用 id 为键）在会话行进入列表镜像时出生，随 prune 死亡。契约：api-contracts v3 §4。每个 `Session` 持有一个通用的 `ProjectionValueStore`，由历史尾页的 `projections` 块播种，并经 `session/projection` 帧按 seq 高者胜更新；领域键（含 `todos` 与 `title`）经 `projections.faceOf`／`useProjection` 读取，不经 `ConversationSnapshot`。持久的 `ConversationSnapshot.metrics` 则来自独立的 history 尾页值与实时 `session/metrics` 帧，因为即时 token-meter 压力可以在相同持久日志修订号上继续变化；客户端只接受日志修订号与投影修订号均不减小的数据。`ConversationSnapshot.modelRequestContextWindow` 另行保留当前 mux 连接观察到的最新 `session/model-request` 容量。后续请求会替换或清除该值，`session/subscribed` 则同时清除指标顺序状态与容量；因此，重连、恢复和新订阅都不会显示百分比，直到观察到另一次请求。缺失的 metrics 保持为 `null`，而不是根据可见节点窗口推断。
+客户端 cordis 启动与不依赖 React 的对象服务：SlotsService 包装 SlotCore 并提供 renderer 数据源；SessionsService 拥有 Session 对象、列表／scope／history 状态；WorkspacesService 依赖 SessionsService，拥有 Workspace 对象、列表／操作、默认目标派生，以及 New Session 空会话复用入口（`connectWorkspace`）。运行时把共享 Host 流分发给两个 manager。客户端 Session 一律由 Host 出生（一次 `session.create` 同瞬产出 Session+Agent+cwd）；客户端不持有任何实体化之前的会话状态——Agent scope（host dsh-scope 的客户端镜像，以 agent/session 共用 id 为键）在会话行进入列表镜像时出生，随 prune 死亡。契约：api-contracts v3 §4。每个 `Session` 持有一个通用的 `ProjectionValueStore`，由历史尾页的 `projections` 块播种，并经 `session/projection` 帧按 seq 高者胜更新；领域键（含 `todos`、`title` 与 `tokenUsage`）经 `projections.faceOf`／`useProjection` 读取，不经 `ConversationSnapshot`。`ConversationSnapshot.modelRequest` 另行保留当前 mux 连接观察到的最新完整 `session/model-request`。每个帧都会替换整个快照，因此分子或容量字段一旦缺失，就会清除先前值。`SessionManager` 会缓冲一个实例化前快照；`session/subscribed`、断开连接和移除会话则会清除常驻值与待处理值；因此，重连、恢复和新订阅都不会显示上下文百分比，直到观察到另一次请求。仅选择模型不会改变请求观测数据。

 ## Workspace 与 Session 列表

--- a/packages/client/runtime/src/client/sessions/conversation.ts
+++ b/packages/client/runtime/src/client/sessions/conversation.ts
@@ -6,7 +6,7 @@
 import type { CommandId } from '@deepseek-ai/dsh-commands/brand'
 import type { ContentBlock } from '@deepseek-ai/dsh-llm/types'
 import type {
-  RpcError, SessionId, SessionMetrics, ToolCallView, ToolResultView,
+  ModelRequestTelemetry, RpcError, SessionId, ToolCallView, ToolResultView,
 } from '@deepseek-ai/dsh-client-connection/client'
 import type { PendingInteraction } from './pending.ts'

@@ -267,16 +267,6 @@ export interface ConversationSnapshot {
   */
  blank: boolean
  lastAgentError: string | null
-  /**
-   * Host-owned cumulative usage/current pressure. Independent of `nodes`
-   * pagination; null until a tail response or live metrics frame supplies a
-   * current durable value.
-   */
-  metrics: SessionMetrics | null
-  /**
-   * Capacity from the latest model-request attempt observed on this mux
-   * generation. Absent before the first such request, after a request whose
-   * registration exposes no capacity, and after `session/subscribed`.
-   */
-  modelRequestContextWindow?: number
+  /** Latest atomic model-request snapshot on this mux generation. */
+  modelRequest: ModelRequestTelemetry | null
 }
--- a/packages/client/runtime/src/client/sessions/manager.ts
+++ b/packages/client/runtime/src/client/sessions/manager.ts
@@ -2,7 +2,10 @@
 // dispatch entry + list state, constructed and held by SessionsService (one per client runtime).
 // List data never enters zustand; React connects via subscribe/getListSnapshot.

-import type { IApiClient, HostFrame, MuxFrame, RpcError, RpcRequest, RpcResult, SessionId, SessionSummary, WorkspaceId } from '@deepseek-ai/dsh-client-connection/client'
+import type {
+  HostFrame, IApiClient, ModelRequestTelemetry, MuxFrame, RpcError, RpcRequest,
+  RpcResult, SessionId, SessionSummary, WorkspaceId,
+} from '@deepseek-ai/dsh-client-connection/client'
 // Value import from the inline-safe wire layer (not the connection plugin):
 // plugin-to-plugin value imports are a bundle purity error.
 import { transportError } from '@deepseek-ai/dsh-host-apiproxy/api'
@@ -58,11 +61,11 @@ export class SessionManager {
   *  frames are low-frequency; overflow drops oldest) and dropped on session-removed (audit S7). */
  private readonly pendingBuffers = new Map<SessionId, RpcRequest<MuxFrame>[]>()
  /**
-   * Latest model capacity observed for an uninstantiated session on the
+   * Latest request telemetry observed for an uninstantiated session on the
   * current mux generation. Unlike durable history, this transient frame
   * cannot be backfilled when get() lazily creates the Session.
   */
-  private readonly modelRequestContextWindows = new Map<SessionId, number>()
+  private readonly modelRequests = new Map<SessionId, ModelRequestTelemetry>()
  /** Outstanding approval questions per session, keyed by approvalId (idempotent under mux-open
   *  replays of the same requested frame). Manager-owned rather than read off Session instances
   *  because the sidebar must light up for sessions never instantiated. Cleared per connection
@@ -171,7 +174,7 @@ export class SessionManager {
  }

  private createSession(sessionId: SessionId): Session {
-    const modelRequestContextWindow = this.modelRequestContextWindows.get(sessionId)
+    const modelRequest = this.modelRequests.get(sessionId)
    return new Session(sessionId, this.api, {
      // The sender's local first-send flip mirrors into the list row so the
      // session surfaces (lists filter on blank) before any host frame lands.
@@ -179,7 +182,7 @@ export class SessionManager {
        this.recordMutation({ kind: 'engaged', sessionId: engaged.sessionId })
      },
      projections: this.projectionStore(sessionId),
-      ...(modelRequestContextWindow === undefined ? {} : { modelRequestContextWindow }),
+      ...(modelRequest === undefined ? {} : { modelRequest }),
    })
  }

@@ -355,13 +358,13 @@ export class SessionManager {
      return
    }
    if (frame.type === 'session/model-request') {
-      // Transient and non-replayable: retain the latest capacity until lazy
-      // instantiation. An absent value explicitly clears an earlier one.
-      if (frame.contextWindow === undefined) this.modelRequestContextWindows.delete(frame.sessionId)
-      else this.modelRequestContextWindows.set(frame.sessionId, frame.contextWindow)
+      // Transient and non-replayable: retain the whole latest request until
+      // lazy instantiation. Missing fields replace rather than inherit.
+      const { type: _type, sessionId, ...modelRequest } = frame
+      this.modelRequests.set(sessionId, modelRequest)
    }
    if (frame.type === 'session/subscribed') {
-      this.modelRequestContextWindows.delete(frame.sessionId)
+      this.modelRequests.delete(frame.sessionId)
      // Rows past the host's durable baseline rode state a restart lost; drop
      // them so last-wins cannot pin a phantom value over recomputed truth.
      this.projectionStores.get(frame.sessionId)?.truncate(frame.lastSeq)
@@ -440,7 +443,7 @@ export class SessionManager {
        this.recordMutation({ kind: 'remove', sessionId: frame.sessionId })
        this.sessions.get(frame.sessionId)?.handleRemoved() // instance survives (resident-instance rule), only flagged in the snapshot
        this.pendingBuffers.delete(frame.sessionId) // a removed session's buffered frames must not replay on a future instantiation
-        this.modelRequestContextWindows.delete(frame.sessionId) // connection-local request capacity dies with the Host session
+        this.modelRequests.delete(frame.sessionId) // connection-local request telemetry dies with the Host session
        this.waitingApprovals.delete(frame.sessionId) // a removed session cannot wait on anyone
        this.projectionStores.delete(frame.sessionId) // removed sessions drop their projection rows with the instance
        return
@@ -481,7 +484,7 @@ export class SessionManager {
      if (kept.length === 0) this.pendingBuffers.delete(sessionId)
      else this.pendingBuffers.set(sessionId, kept)
    }
-    this.modelRequestContextWindows.clear()
+    this.modelRequests.clear()
    for (const session of this.sessions.values()) session.handleReconnecting()
  }

--- a/packages/client/runtime/src/client/sessions/session.ts
+++ b/packages/client/runtime/src/client/sessions/session.ts
@@ -5,7 +5,7 @@ import type { ContentBlock } from '@deepseek-ai/dsh-llm/types'
 import type { SessionEvent } from '@deepseek-ai/dsh-session/types'
 import type {
  HistoryEntry, IApiClient, MuxFrame, RpcError, RpcId, RpcResult,
-  SessionId, SessionMetrics, ToolEventView,
+  ModelRequestTelemetry, SessionId, ToolEventView,
 } from '@deepseek-ai/dsh-client-connection/client'
 // Value import from the inline-safe wire layer (not the connection plugin):
 // plugin-to-plugin value imports are a bundle purity error.
@@ -43,8 +43,8 @@ export interface SessionOptions {
   * private store (bare object-layer construction).
   */
  projections?: ProjectionValueStore
-  /** Model capacity already observed on this mux generation before lazy construction. */
-  modelRequestContextWindow?: number
+  /** Request telemetry already observed on this mux generation before lazy construction. */
+  modelRequest?: ModelRequestTelemetry
 }

 /** Queue-row preview cap: the dock renders one line, the full content never leaves the host mirror. */
@@ -110,10 +110,8 @@ export class Session implements SessionFace {
  private queueCache: { rev: number; value: QueuedMessage[] } | null = null
  private frozenRev = 0
  private nodesCache: { folded: readonly ConversationNode[]; frozenRev: number; value: readonly ConversationNode[] } | null = null
-  /** Host-owned durable usage/current-pressure projection. */
-  private metrics: SessionMetrics | null = null
-  /** Latest capacity observed on this mux connection, independent of durable metrics arrival. */
-  private contextWindow: number | undefined
+  /** Latest atomic request snapshot observed on this mux connection. */
+  private modelRequest: ModelRequestTelemetry | null
  /** `run_code` sub-dispatches by parent callId (window-derived, like openCalls). Appends
   *  copy-on-write the per-parent array so published snapshot references never mutate. */
  private codeDispatches = new Map<string, readonly CodeSubCall[]>()
@@ -175,7 +173,7 @@ export class Session implements SessionFace {
    private readonly options: SessionOptions = {},
  ) {
    this.projections = options.projections ?? new ProjectionValueStore()
-    this.contextWindow = options.modelRequestContextWindow
+    this.modelRequest = options.modelRequest ?? null
    this.snapshotCache = this.buildSnapshot()
  }

@@ -331,10 +329,10 @@ export class Session implements SessionFace {
   *  in-flight open first — its history request rode the dead connection and must not settle
   *  the fresh generation into 'error' (audit S4). */
  async resync(): Promise<void> {
-    // Queue, metrics, and request capacity are NOT cleared here: onConnected
+    // Queue and request telemetry are NOT cleared here: onConnected
    // (which drives resync) races the mux frames — fresh-generation state may
-    // have landed already, and the host never resends it. session/subscribed
-    // owns the generation reset before the queue snapshot and metrics frames.
+    // have landed already, and the host never resends request telemetry.
+    // session/subscribed owns the reset before the queue snapshot.
    if (this.openState === 'cold') return // never opened: no window to rebuild (doOpen flips to 'loading' synchronously, so cold implies no in-flight open)
    this.openGeneration++
    this.openPromise = null
@@ -415,24 +413,22 @@ export class Session implements SessionFace {
          this.queueRev++
          changed = true
        }
-        if (this.contextWindow !== undefined) {
-          this.contextWindow = undefined
-          changed = true
-        }
-        if (this.metrics !== null) {
-          this.metrics = null
+        if (this.modelRequest !== null) {
+          this.modelRequest = null
          changed = true
        }
        if (changed) this.notifier.markDirty()
        return
      }
-      case 'session/metrics': {
-        this.installMetrics(frame.metrics)
-        return
-      }
      case 'session/model-request': {
-        if (this.contextWindow === frame.contextWindow) return
-        this.contextWindow = frame.contextWindow
+        const {
+          type: _type,
+          sessionId: _sessionId,
+          ...modelRequest
+        } = frame
+        // Whole-frame replacement is load-bearing: an omitted numerator or
+        // capacity clears that field from the preceding request.
+        this.modelRequest = modelRequest
        this.notifier.markDirty()
        return
      }
@@ -508,17 +504,16 @@ export class Session implements SessionFace {
  /** Connection-loss boundary: clear values that are not replayed before the next stream starts. */
  handleReconnecting(): void {
    this.openGeneration++
-    if (this.metrics === null && this.contextWindow === undefined) return
-    this.metrics = null
-    this.contextWindow = undefined
+    if (this.modelRequest === null) return
+    this.modelRequest = null
    this.notifier.markDirty()
  }

-  /** host/session-removed relay: flag the resident snapshot and clear connection-local capacity. */
+  /** host/session-removed relay: flag the resident snapshot and clear request telemetry. */
  handleRemoved(): void {
-    const changed = !this.removed || this.contextWindow !== undefined
+    const changed = !this.removed || this.modelRequest !== null
    this.removed = true
-    this.contextWindow = undefined
+    this.modelRequest = null
    if (changed) this.notifier.markDirty()
  }

@@ -567,7 +562,6 @@ export class Session implements SessionFace {
        result.value.events,
        result.value.hasMore,
        result.value.projections,
-        result.value.metrics,
      )
      // Gap detection (§D.3-4): baseline past the window tail and liveBuffer did not cover it -> pull the tail page once more.
      const tailSeq = this.windowTailSeq()
@@ -579,7 +573,6 @@ export class Session implements SessionFace {
            result.value.events,
            result.value.hasMore,
            result.value.projections,
-            result.value.metrics,
          )
        }
      }
@@ -606,7 +599,6 @@ export class Session implements SessionFace {
    entries: HistoryEntry[],
    hasMore: boolean,
    projections: ProjectionsBaseline | undefined,
-    metrics: SessionMetrics | undefined,
  ): void {
    this.events = entries.map(e => e.event)
    this.views = entries.map(e => e.view)
@@ -615,7 +607,6 @@ export class Session implements SessionFace {
    this.foldAdapter.reset(this.events, this.baseSeq, this.views)
    this.rebuildDerivedFromWindow()
    if (projections !== undefined) this.projections.seed(projections)
-    if (metrics !== undefined) this.installMetrics(metrics)
    const buffered = this.liveBuffer
    this.liveBuffer = []
    for (const item of buffered) this.appendLive(item.event, item.view)
@@ -668,7 +659,6 @@ export class Session implements SessionFace {
          result.value.events,
          result.value.hasMore,
          result.value.projections,
-          result.value.metrics,
        )
      }
    } catch (error) {
@@ -854,20 +844,6 @@ export class Session implements SessionFace {
    return tail === undefined ? null : tail.seq
  }

-  /** Install a metrics snapshot unless a newer durable or publication revision already landed. */
-  private installMetrics(metrics: SessionMetrics): void {
-    const current = this.metrics
-    if (
-      current !== null
-      && (
-        metrics.logRevision < current.logRevision
-        || metrics.projectionRevision < current.projectionRevision
-      )
-    ) return
-    this.metrics = metrics
-    this.notifier.markDirty()
-  }
-
  private buildSnapshot(): ConversationSnapshot {
    const { nodes: folded, degraded } = this.foldAdapter.nodes()
    // Frozen interrupted nodes ride fractional seqs: a stable merge keeps them in flow order.
@@ -920,10 +896,7 @@ export class Session implements SessionFace {
      promptError: this.promptError,
      blank: this.blankBit,
      lastAgentError: this.lastAgentError,
-      metrics: this.metrics,
-      ...(this.contextWindow === undefined
-        ? {}
-        : { modelRequestContextWindow: this.contextWindow }),
+      modelRequest: this.modelRequest,
    }
  }
 }
--- a/packages/client/runtime/tests/client-apply.spec.ts
+++ b/packages/client/runtime/tests/client-apply.spec.ts
@@ -102,7 +102,7 @@ describe('runtime client apply', () => {
    expect(bench.api.callsOf('session.create')).toHaveLength(1)
  })

-  it('clears connection-local Session state on disconnect but not connected', async () => {
+  it('clears connection-local request telemetry on reconnect but not connected', async () => {
    const bench = await mount()
    const sessions = bench.ctx.get('sessions') as SessionsService
    bench.sinks?.onHostEnvelope?.({
@@ -112,21 +112,8 @@ describe('runtime client apply', () => {
    await Promise.resolve()
    const session = sessions.binding('s-state' as never)?.session
    if (session === undefined) throw new Error('session binding missing')
-    const currentMetrics = {
-      projectionRevision: 4,
-      logRevision: 10,
-      uncachedInputTokens: 10,
-      outputTokens: 4,
-      cacheReadTokens: 90,
-      cacheWriteTokens: 3,
-      contextTokens: 35,
-    }
    bench.sinks?.onMuxEnvelope?.({
-      rpcId: 'metrics' as never,
-      payload: { type: 'session/metrics', sessionId: 's-state', metrics: currentMetrics } as never,
-    })
-    bench.sinks?.onMuxEnvelope?.({
-      rpcId: 'capacity' as never,
+      rpcId: 'request' as never,
      payload: {
        type: 'session/model-request',
        sessionId: 's-state',
@@ -134,19 +121,20 @@ describe('runtime client apply', () => {
        step: 1,
        provider: 'test',
        model: 'alpha',
+        contextTokens: 32_000,
        contextWindow: 128_000,
      } as never,
    })

    bench.sinks?.onConnected?.()
-    expect(session.getSnapshot()).toMatchObject({
-      metrics: currentMetrics,
-      modelRequestContextWindow: 128_000,
+    expect(session.getSnapshot().modelRequest).toMatchObject({
+      model: 'alpha',
+      contextTokens: 32_000,
+      contextWindow: 128_000,
    })

-    bench.sinks?.onDisconnected?.()
-    expect(session.getSnapshot().metrics).toBeNull()
-    expect(session.getSnapshot().modelRequestContextWindow).toBeUndefined()
+    bench.sinks?.onStateChange?.('reconnecting')
+    expect(session.getSnapshot().modelRequest).toBeNull()
  })

  it('stops the stream loop when the plugin fiber unloads', async () => {
--- a/packages/client/runtime/tests/fake-api.ts
+++ b/packages/client/runtime/tests/fake-api.ts
@@ -4,7 +4,7 @@
 import type { CommandId } from '@deepseek-ai/dsh-commands/brand'
 import type {
  ClientResponse, CommandDescriptor, HostFrame, IApiClient, ModelTarget, MuxFrame,
-  RpcError, RpcReceipt, RpcRequest, RpcResponse, SessionId, SessionMetrics, SessionModels,
+  RpcError, RpcReceipt, RpcRequest, RpcResponse, SessionId, SessionModels,
  SessionProjectionsBlock, SkillEntry,
  WorkspaceId, WorkspaceView,
 } from '@deepseek-ai/dsh-client-connection/client'
@@ -69,7 +69,6 @@ export class FakeApiClient implements IApiClient {
    events: never[]
    hasMore: boolean
    projections?: SessionProjectionsBlock
-    metrics?: SessionMetrics
  }>> =
    () => Promise.resolve(ok({ events: [], hasMore: false }))

--- a/packages/client/runtime/tests/manager.spec.ts
+++ b/packages/client/runtime/tests/manager.spec.ts
@@ -4,7 +4,7 @@
 */

 import { describe, expect, it, vi } from 'vitest'
-import type { SessionId, SessionMetrics } from '@deepseek-ai/dsh-client-connection/client'
+import type { SessionId } from '@deepseek-ai/dsh-client-connection/client'
 import { SessionManager } from '../src/client/sessions/manager.ts'
 import { FakeApiClient, deferred, err, ok } from './fake-api.ts'
 import { entries, plainTurn } from './event-script.ts'
@@ -41,7 +41,7 @@ describe('instances', () => {
    expect(manager.get(S2).getSnapshot().pending).toEqual([])
  })

-  it('retains the latest transient model capacity until lazy instantiation', () => {
+  it('retains the latest transient request snapshot until lazy instantiation', () => {
    const api = new FakeApiClient()
    const manager = new SessionManager(api)
    manager.handleMuxEnvelope({
@@ -53,6 +53,7 @@ describe('instances', () => {
        step: 1,
        provider: 'test',
        model: 'alpha',
+        contextTokens: 12_000,
        contextWindow: 128_000,
      },
    })
@@ -65,14 +66,22 @@ describe('instances', () => {
        step: 2,
        provider: 'test',
        model: 'beta',
+        contextTokens: 32_000,
        contextWindow: 256_000,
      },
    })

-    expect(manager.get(S1).getSnapshot().modelRequestContextWindow).toBe(256_000)
+    expect(manager.get(S1).getSnapshot().modelRequest).toEqual({
+      turn: 1,
+      step: 2,
+      provider: 'test',
+      model: 'beta',
+      contextTokens: 32_000,
+      contextWindow: 256_000,
+    })
  })

-  it('retains explicit capacity clearing before lazy instantiation', () => {
+  it('retains whole-frame replacement before lazy instantiation', () => {
    const api = new FakeApiClient()
    const manager = new SessionManager(api)
    manager.handleMuxEnvelope({
@@ -99,10 +108,15 @@ describe('instances', () => {
      },
    })

-    expect(manager.get(S1).getSnapshot().modelRequestContextWindow).toBeUndefined()
+    expect(manager.get(S1).getSnapshot().modelRequest).toEqual({
+      turn: 1,
+      step: 2,
+      provider: 'test',
+      model: 'unknown-capacity',
+    })
  })

-  it('clears retained capacity on subscribed and resident capacity on removal', () => {
+  it('clears retained request telemetry on subscribed and removal', () => {
    const api = new FakeApiClient()
    const manager = new SessionManager(api)
    manager.handleMuxEnvelope({
@@ -122,7 +136,7 @@ describe('instances', () => {
      payload: { type: 'session/subscribed', sessionId: S1, lastSeq: 0 },
    })
    const session = manager.get(S1)
-    expect(session.getSnapshot().modelRequestContextWindow).toBeUndefined()
+    expect(session.getSnapshot().modelRequest).toBeNull()

    manager.handleMuxEnvelope({
      rpcId: 'request-after-subscribe' as never,
@@ -136,12 +150,12 @@ describe('instances', () => {
        contextWindow: 256_000,
      },
    })
-    expect(session.getSnapshot().modelRequestContextWindow).toBe(256_000)
+    expect(session.getSnapshot().modelRequest?.contextWindow).toBe(256_000)
    manager.handleHostEnvelope({
      rpcId: 'removed' as never,
      payload: { type: 'host/session-removed', sessionId: S1 },
    })
-    expect(session.getSnapshot().modelRequestContextWindow).toBeUndefined()
+    expect(session.getSnapshot().modelRequest).toBeNull()

    manager.handleMuxEnvelope({
      rpcId: 'request-before-lazy-removal' as never,
@@ -159,28 +173,15 @@ describe('instances', () => {
      rpcId: 'lazy-removed' as never,
      payload: { type: 'host/session-removed', sessionId: S2 },
    })
-    expect(manager.get(S2).getSnapshot().modelRequestContextWindow).toBeUndefined()
+    expect(manager.get(S2).getSnapshot().modelRequest).toBeNull()
  })

-  it('clears resident metrics and capacity plus lazy capacity before reconnect', () => {
+  it('clears resident and lazy request telemetry on disconnect', () => {
    const api = new FakeApiClient()
    const manager = new SessionManager(api)
    const session = manager.get(S1)
-    const currentMetrics: SessionMetrics = {
-      projectionRevision: 4,
-      logRevision: 10,
-      uncachedInputTokens: 10,
-      outputTokens: 4,
-      cacheReadTokens: 90,
-      cacheWriteTokens: 3,
-      contextTokens: 35,
-    }
    manager.handleMuxEnvelope({
-      rpcId: 'metrics' as never,
-      payload: { type: 'session/metrics', sessionId: S1, metrics: currentMetrics },
-    })
-    manager.handleMuxEnvelope({
-      rpcId: 'resident-capacity' as never,
+      rpcId: 'resident-request' as never,
      payload: {
        type: 'session/model-request',
        sessionId: S1,
@@ -188,11 +189,12 @@ describe('instances', () => {
        step: 1,
        provider: 'test',
        model: 'resident',
+        contextTokens: 35,
        contextWindow: 128_000,
      },
    })
    manager.handleMuxEnvelope({
-      rpcId: 'lazy-capacity' as never,
+      rpcId: 'lazy-request' as never,
      payload: {
        type: 'session/model-request',
        sessionId: S2,
@@ -200,19 +202,20 @@ describe('instances', () => {
        step: 1,
        provider: 'test',
        model: 'lazy',
+        contextTokens: 70,
        contextWindow: 256_000,
      },
    })
-    expect(session.getSnapshot()).toMatchObject({
-      metrics: currentMetrics,
-      modelRequestContextWindow: 128_000,
+    expect(session.getSnapshot().modelRequest).toMatchObject({
+      model: 'resident',
+      contextTokens: 35,
+      contextWindow: 128_000,
    })

-    manager.handleReconnecting()
+    manager.handleDisconnected()

-    expect(session.getSnapshot().metrics).toBeNull()
-    expect(session.getSnapshot().modelRequestContextWindow).toBeUndefined()
-    expect(manager.get(S2).getSnapshot().modelRequestContextWindow).toBeUndefined()
+    expect(session.getSnapshot().modelRequest).toBeNull()
+    expect(manager.get(S2).getSnapshot().modelRequest).toBeNull()
  })

  it('caps the pending buffer at 32 keeping the newest, and drops it on session-removed', () => {
--- a/packages/client/runtime/tests/session.spec.ts
+++ b/packages/client/runtime/tests/session.spec.ts
@@ -10,7 +10,7 @@ import { describe, expect, it, vi } from 'vitest'
 import { Context } from 'cordis'
 import type { SessionEvent } from '@deepseek-ai/dsh-session/types'
 import type {
-  SessionId, SessionMetrics, SessionProjectionsBlock,
+  SessionId, SessionProjectionsBlock,
 } from '@deepseek-ai/dsh-client-connection/client'
 import { Session } from '../src/client/sessions/session.ts'
 import { FakeApiClient, deferred, err, ok } from './fake-api.ts'
@@ -29,34 +29,15 @@ function histResponse(
  events: SessionEvent[],
  hasMore = false,
  projections?: SessionProjectionsBlock,
-  metrics?: SessionMetrics,
 ) {
  // history now returns HistoryEntry[] ({event, view?}); these tests are view-less.
  return Promise.resolve(ok({
    events: entries(events) as never[],
    hasMore,
    ...projections === undefined ? {} : { projections },
-    ...metrics === undefined ? {} : { metrics },
  }))
 }

-function metrics(
-  projectionRevision: number,
-  logRevision: number,
-  over: Partial<SessionMetrics> = {},
-): SessionMetrics {
-  return {
-    projectionRevision,
-    logRevision,
-    uncachedInputTokens: 10,
-    outputTokens: 4,
-    cacheReadTokens: 90,
-    cacheWriteTokens: 3,
-    contextTokens: 35,
-    ...over,
-  }
-}
-
 describe('open', () => {
  it('installs the tail page: cold → loading → open with window and nodes in place', async () => {
    const { api, session } = makeSession()
@@ -70,19 +51,7 @@ describe('open', () => {
    expect(snapshot.openState).toBe('open')
    expect(snapshot.hasMore).toBe(true)
    expect(snapshot.nodes.map(n => n.kind)).toEqual(['user', 'assistant'])
-    expect(snapshot.metrics).toBeNull()
-  })
-
-  it('installs full-log metrics independently of older history pages', async () => {
-    const { api, session } = makeSession()
-    const tailMetrics = metrics(4, 106)
-    api.onHistory = () => histResponse(plainTurn(100, 3, '问', '答'), true, undefined, tailMetrics)
-    await session.open()
-    expect(session.getSnapshot().metrics).toBe(tailMetrics)
-
-    api.onHistory = () => histResponse(plainTurn(94, 2, '旧问', '旧答'))
-    await session.loadOlder()
-    expect(session.getSnapshot().metrics).toBe(tailMetrics)
+    expect(snapshot.modelRequest).toBeNull()
  })

  it('is idempotent: concurrent opens share one history call, reopening when open is a no-op', async () => {
@@ -147,17 +116,8 @@ describe('live event path', () => {
    expect(session.getSnapshot().nodes).toEqual(before.nodes)
  })

-  it('keeps live capacity separate from durable metrics, replaces or clears it on requests, and resets at subscription', async () => {
+  it('replaces the whole request snapshot, clears omitted fields, and resets at subscription', async () => {
    const { session } = await opened()
-    const current = metrics(8, 10)
-    session.handleMuxEnvelope('m1' as never, {
-      type: 'session/metrics',
-      sessionId: SID,
-      metrics: current,
-    })
-    expect(session.getSnapshot().metrics).toBe(current)
-    expect(session.getSnapshot().modelRequestContextWindow).toBeUndefined()
-
    session.handleMuxEnvelope('request-1' as never, {
      type: 'session/model-request',
      sessionId: SID,
@@ -165,32 +125,17 @@ describe('live event path', () => {
      step: 1,
      provider: 'test',
      model: 'alpha',
+      contextTokens: 32_000,
      contextWindow: 128_000,
    })
-    expect(session.getSnapshot().metrics).toBe(current)
-    expect(session.getSnapshot().modelRequestContextWindow).toBe(128_000)
-
-    session.handleMuxEnvelope('m2' as never, {
-      type: 'session/metrics',
-      sessionId: SID,
-      metrics: metrics(9, 9, { uncachedInputTokens: 1 }),
+    expect(session.getSnapshot().modelRequest).toEqual({
+      turn: 1,
+      step: 1,
+      provider: 'test',
+      model: 'alpha',
+      contextTokens: 32_000,
+      contextWindow: 128_000,
    })
-    session.handleMuxEnvelope('m3' as never, {
-      type: 'session/metrics',
-      sessionId: SID,
-      metrics: metrics(7, 11, { uncachedInputTokens: 2 }),
-    })
-    expect(session.getSnapshot().metrics).toBe(current)
-    expect(session.getSnapshot().modelRequestContextWindow).toBe(128_000)
-
-    const ordinaryUpdate = metrics(9, 11, { contextTokens: 40 })
-    session.handleMuxEnvelope('m4' as never, {
-      type: 'session/metrics',
-      sessionId: SID,
-      metrics: ordinaryUpdate,
-    })
-    expect(session.getSnapshot().metrics).toBe(ordinaryUpdate)
-    expect(session.getSnapshot().modelRequestContextWindow).toBe(128_000)

    session.handleMuxEnvelope('request-2' as never, {
      type: 'session/model-request',
@@ -200,16 +145,19 @@ describe('live event path', () => {
      provider: 'test',
      model: 'without-capacity',
    })
-    expect(session.getSnapshot().metrics).toEqual(ordinaryUpdate)
-    expect(session.getSnapshot().modelRequestContextWindow).toBeUndefined()
+    expect(session.getSnapshot().modelRequest).toEqual({
+      turn: 2,
+      step: 1,
+      provider: 'test',
+      model: 'without-capacity',
+    })

    session.handleMuxEnvelope('sub' as never, {
      type: 'session/subscribed',
      sessionId: SID,
      lastSeq: 5,
    })
-    expect(session.getSnapshot().metrics).toBeNull()
-    expect(session.getSnapshot().modelRequestContextWindow).toBeUndefined()
+    expect(session.getSnapshot().modelRequest).toBeNull()
    session.handleMuxEnvelope('request-3' as never, {
      type: 'session/model-request',
      sessionId: SID,
@@ -217,19 +165,17 @@ describe('live event path', () => {
      step: 1,
      provider: 'test',
      model: 'beta',
+      contextTokens: 20,
      contextWindow: 256_000,
    })
-    const nextGeneration = metrics(0, 10, { contextTokens: 20 })
-    session.handleMuxEnvelope('m5' as never, {
-      type: 'session/metrics',
-      sessionId: SID,
-      metrics: nextGeneration,
+    expect(session.getSnapshot().modelRequest).toMatchObject({
+      turn: 3,
+      contextTokens: 20,
+      contextWindow: 256_000,
    })
-    expect(session.getSnapshot().metrics).toBe(nextGeneration)
-    expect(session.getSnapshot().modelRequestContextWindow).toBe(256_000)
  })

-  it('publishes a subscribed reset when capacity arrived before durable metrics', async () => {
+  it('publishes a subscribed reset when request telemetry arrived first', async () => {
    const { session } = await opened()
    session.handleMuxEnvelope('request' as never, {
      type: 'session/model-request',
@@ -238,17 +184,17 @@ describe('live event path', () => {
      step: 1,
      provider: 'test',
      model: 'alpha',
+      contextTokens: 8_000,
      contextWindow: 128_000,
    })
-    expect(session.getSnapshot().metrics).toBeNull()
-    expect(session.getSnapshot().modelRequestContextWindow).toBe(128_000)
+    expect(session.getSnapshot().modelRequest?.contextWindow).toBe(128_000)

    session.handleMuxEnvelope('sub' as never, {
      type: 'session/subscribed',
      sessionId: SID,
      lastSeq: 5,
    })
-    expect(session.getSnapshot().modelRequestContextWindow).toBeUndefined()
+    expect(session.getSnapshot().modelRequest).toBeNull()
  })

  it('materializes a command node from live lifecycle frames and reproduces it from a history window', async () => {
@@ -876,72 +822,61 @@ describe('remaining branches', () => {
 })

 describe('resync', () => {
-  it('fences pre-disconnect history behind a fresh mux metrics baseline', async () => {
+  it('clears request telemetry on reconnect and drops a stale in-flight history response', async () => {
    const { api, session } = makeSession()
    const stale = deferred<Awaited<ReturnType<FakeApiClient['onHistory']>>>()
    api.onHistory = () => stale.promise
    const opening = session.open()
-    const oldLiveMetrics = metrics(8, 10)
-    session.handleMuxEnvelope('old-metrics' as never, {
-      type: 'session/metrics',
-      sessionId: SID,
-      metrics: oldLiveMetrics,
-    })
-    session.handleMuxEnvelope('old-capacity' as never, {
+    session.handleMuxEnvelope('old-request' as never, {
      type: 'session/model-request',
      sessionId: SID,
      turn: 1,
      step: 1,
      provider: 'test',
      model: 'old',
+      contextTokens: 20,
      contextWindow: 128_000,
    })

    session.handleReconnecting()
-    expect(session.getSnapshot().metrics).toBeNull()
-    expect(session.getSnapshot().modelRequestContextWindow).toBeUndefined()
-    const freshMetrics = metrics(0, 1, { contextTokens: 20 })
-    session.handleMuxEnvelope('fresh-metrics' as never, {
-      type: 'session/metrics',
-      sessionId: SID,
-      metrics: freshMetrics,
-    })
+    expect(session.getSnapshot().modelRequest).toBeNull()

    stale.resolve(ok({
      events: entries(plainTurn(0, 0, '旧问', '旧答')) as never[],
      hasMore: false,
-      metrics: metrics(99, 99, { contextTokens: 999 }),
    }))
    await opening
    expect(session.getSnapshot().nodes).toEqual([])
-    expect(session.getSnapshot().metrics).toBe(freshMetrics)
+    expect(session.getSnapshot().modelRequest).toBeNull()

    api.onHistory = () => histResponse(plainTurn(6, 1, '新问', '新答'))
    await session.resync()
    expect(session.getSnapshot().openState).toBe('open')
    expect(session.getSnapshot().nodes.map(node => node.seq)).toEqual([7, 9])
-    expect(session.getSnapshot().metrics).toBe(freshMetrics)
+    expect(session.getSnapshot().modelRequest).toBeNull()
  })

-  it('preserves fresh-generation metrics that arrive before a failing history refresh', async () => {
+  it('preserves a fresh-generation request snapshot when history resync fails', async () => {
    const { api, session } = makeSession()
-    const oldMetrics = metrics(8, 10)
-    api.onHistory = () => histResponse(plainTurn(0, 0, 'a', 'b'), false, undefined, oldMetrics)
+    api.onHistory = () => histResponse(plainTurn(0, 0, 'a', 'b'))
    await session.open()
-    expect(session.getSnapshot().metrics).toBe(oldMetrics)

    session.handleMuxEnvelope('sub' as never, {
      type: 'session/subscribed',
      sessionId: SID,
      lastSeq: 5,
    })
-    expect(session.getSnapshot().metrics).toBeNull()
+    expect(session.getSnapshot().modelRequest).toBeNull()

-    const freshMetrics = metrics(0, 10, { contextTokens: 20 })
-    session.handleMuxEnvelope('fresh-metrics' as never, {
-      type: 'session/metrics',
+    session.handleMuxEnvelope('fresh-request' as never, {
+      type: 'session/model-request',
      sessionId: SID,
-      metrics: freshMetrics,
+      turn: 2,
+      step: 1,
+      provider: 'test',
+      model: 'fresh',
+      contextTokens: 20,
+      contextWindow: 256_000,
    })
    api.onHistory = () => Promise.resolve(err({
      code: 'internal',
@@ -953,7 +888,14 @@ describe('resync', () => {

    expect(session.getSnapshot()).toMatchObject({
      openState: 'error',
-      metrics: freshMetrics,
+      modelRequest: {
+        turn: 2,
+        step: 1,
+        provider: 'test',
+        model: 'fresh',
+        contextTokens: 20,
+        contextWindow: 256_000,
+      },
    })
  })

--- a/packages/client/test-runtime/src/fixtures.ts
+++ b/packages/client/test-runtime/src/fixtures.ts
@@ -62,6 +62,7 @@ export function conversationSnapshot(sessionId: SessionId): ConversationSnapshot
    promptError: null,
    blank: false,
    lastAgentError: null,
+    modelRequest: null,
  }
 }

--- 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: b74127ffe11df40fcad0c97e2fc6896ec79ad9d1
-README.zh.md: f6dfc3ca61ea80758c9f64ca98f034b0832ee89e
+README.md: c60a38ec26d4bca15ce23e51dbaedf3ef36022e4
+README.zh.md: 65c5554a78960fc4f86a6a370772c95429c648c4
--- a/packages/client/ui-conversation/README.md
+++ b/packages/client/ui-conversation/README.md
@@ -20,7 +20,7 @@ Per-session UI state for selection and the active view lives in the declared cha

 The composer bar declares session-scoped single seats for `'conversation.input.plan'` (right of the local access-mode control) and `'conversation.input.model'` (immediately before the pending indicator and send/stop button), plus list slots for overlay, dock, left, and right input extensions. Feature packages own each control and its state; ui-conversation supplies placement, the `locked` owner prop, and the standard slot shares. While the `plan` projection's effective target is plan mode, InputBar swaps its textarea placeholder to the plan-task wording (a host-folded value read through the standard-kit `useProjection`; owner-supplied placeholders win). The resident no-session shell uses `DisabledInputBar` and therefore dispatches no session-scoped control seats.

-The chat stats line reads durable token counters/current pressure from `ConversationSnapshot.metrics` and joins them only at presentation with the separate connection-local `modelRequestContextWindow`; visible nodes supply only the existing turn/step counts. It renders uncached input, output, and cache reads as separate compact values, computes cache hit as `cacheRead / (uncachedInput + cacheRead)` without cache writes, and shows context occupancy only after the current mux connection observes a model request with capacity. Before that request, after reconnect/restore/new subscription, or after a request without capacity, the percentage is omitted and context is labeled unknown rather than queried ahead or reconstructed from history.
+The chat stats line reads full-log billing from the generic `tokenUsage` projection and joins it only at presentation with the connection-local atomic `ConversationSnapshot.modelRequest`; visible nodes supply only the existing turn/step counts. It renders uncached input, output, and cache reads as separate compact values, computes cache hit as `cacheRead / (uncachedInput + cacheRead)` without cache writes, and shows context occupancy only when the same observed request snapshot contains both `contextTokens` and `contextWindow`. Before that request, after reconnect/restore/new subscription, or after a request missing either field, context is labeled unknown rather than queried from the selected model or reconstructed from history. The existing inline stats row remains the sole context UI; the model selector has no circle or accessory.

 `src/client/` is organized for the future package split: `contract/` is the sole inter-domain shared face (`slots.ts` slot declarations + composed slot props including the tool-row contract, `views.ts` shared primitives, `tool-call-model.ts`); the `skeleton/`, `chat/`, and `toolviews/` (sample registrants) domain directories import contract files and never each other; `apply.ts` is the only assembly point allowed to import all three domains. The `/client` export surface is the contract only — `apply`/`inject`, the two service classes, and the `contract/` type families; implementation components (skeleton, chat rows) and the store factory stay internal and reach the page exclusively through apply's slot registrations (tests take them via the `./src/*` subpath).

--- a/packages/client/ui-conversation/README.zh.md
+++ b/packages/client/ui-conversation/README.zh.md
@@ -20,7 +20,7 @@ todo 两个面就是在该形状上的两个注册项，都是普通注册方插

 输入栏为 `'conversation.input.plan'`（位于本地 access 模式控件右侧）和 `'conversation.input.model'`（渲染在 pending 指示器与发送／停止按钮之前）声明会话作用域的单实例 seat，并为 overlay、dock、left 和 right 输入扩展声明列表 slot。各功能包拥有相应控件及其状态；ui-conversation 提供放置位置、`locked` owner prop 和标准 slot share。当 `plan` 投影的有效目标为 plan mode 时，InputBar 将文本框 placeholder 切换为 plan 任务措辞（经标准套件 `useProjection` 读取的 host 折叠值；owner 提供的 placeholder 优先）。常驻无会话壳使用 `DisabledInputBar`，因此不会分发任何会话作用域的控件 seat。

-聊天统计行从 `ConversationSnapshot.metrics` 读取持久的 token 计数／当前压力，并且只在展示时把它们与独立的连接本地 `modelRequestContextWindow` 结合；可见节点仅提供既有的轮次和步骤计数。它以相互独立的紧凑值显示未缓存输入、输出与缓存读取，通过 `cacheRead / (uncachedInput + cacheRead)` 计算缓存命中率而不计入缓存写入，并且只有当前 mux 连接观察到带容量的模型请求后才显示上下文占用率。在该请求之前、重连／恢复／新订阅之后，或在请求不带容量之后，系统都会省略百分比，并把上下文标为「未知」，而不会提前查询或根据历史记录重建。
+聊天统计行从通用 `tokenUsage` 投影读取完整日志计费用量，并且只在展示时把它与连接本地的原子快照 `ConversationSnapshot.modelRequest` 结合；可见节点仅提供既有的轮次和步骤计数。它以相互独立的紧凑值显示未缓存输入、输出与缓存读取，通过 `cacheRead / (uncachedInput + cacheRead)` 计算缓存命中率而不计入缓存写入，并且只有同一份已观测请求快照同时包含 `contextTokens` 与 `contextWindow` 时才显示上下文占用率。在该请求之前、重连／恢复／新订阅之后，或在请求缺少任一字段之后，系统都会把上下文标为「未知」，而不会从所选模型查询或根据历史记录重建。现有的行内统计行仍是唯一的上下文 UI；模型选择器不增加圆环或附属控件。

 `src/client/` 按未来的包拆分组织：`contract/` 是唯一的跨领域共享表层（`slots.ts` slot 声明 + 组合后的 slot props，包括工具行契约、`views.ts` 共享原语、`tool-call-model.ts`）；`skeleton/`、`chat/` 和 `toolviews/`（示例注册方）领域目录只导入 contract 文件，彼此绝不导入；`apply.ts` 是唯一允许导入全部三个领域的组装点。`/client` 导出表层只包含契约：`apply`／`inject`、两个服务类和 `contract/` 类型家族；实现组件（骨架、聊天行）与 store factory 保持内部状态，只能通过 apply 的 slot 注册到达页面（测试通过 `./src/*` 子路径获取它们）。

--- a/packages/client/ui-conversation/package.json
+++ b/packages/client/ui-conversation/package.json
@@ -44,6 +44,7 @@
    "@deepseek-ai/dsh-client-ui-slash": "^0.0.1",
    "@deepseek-ai/dsh-client-ui-slots": "^0.0.1",
    "@deepseek-ai/dsh-invariants": "^0.0.1",
+    "@deepseek-ai/dsh-token-meter": "^0.0.1",
    "cordis": "^4.0.0-rc.7",
    "react": "^18.2.0"
  },
@@ -52,6 +53,7 @@
    "@deepseek-ai/dsh-plan-mode": "workspace:^",
    "@deepseek-ai/dsh-session-projection": "workspace:^",
    "@deepseek-ai/dsh-tool-todo": "workspace:^",
+    "@deepseek-ai/dsh-token-meter": "workspace:^",
    "@deepseek-ai/dsh-client-ui-layout": "workspace:^",
    "@deepseek-ai/dsh-client-ui-primitives": "workspace:^",
    "@deepseek-ai/dsh-client-ui-slash": "workspace:^",
--- a/packages/client/ui-conversation/src/client/chat/ChatView.tsx
+++ b/packages/client/ui-conversation/src/client/chat/ChatView.tsx
@@ -221,7 +221,9 @@ function StreamingTail({ useSession, onGrow }: {
 * The chat view slot entry: pure component over the composed props (tool rows
 * render through the declared keyed hole's renderSlot share).
 */
-export function ChatView({ useSession, useSessions, useStore, renderSlot, sessionId, openFile, loadOlder }: ChatViewSlotProps) {
+export function ChatView({
+  useProjection, useSession, useSessions, useStore, renderSlot, sessionId, openFile, loadOlder,
+}: ChatViewSlotProps) {
  const nodes = useSession(s => s.nodes)
  // Workspace root off the session list row: path summaries display relative to it.
  const cwd = useSessions(s => s.byId[sessionId]?.cwd)
@@ -381,7 +383,7 @@ export function ChatView({ useSession, useSessions, useStore, renderSlot, sessio
          {running && <TurnDots />}
        </div>
      </div>
-      <StatsLine useSession={useSession} />
+      <StatsLine useSession={useSession} useProjection={useProjection} />
      {!atBottom && (
        <button
          type="button"
--- a/packages/client/ui-conversation/src/client/chat/StatsLine.tsx
+++ b/packages/client/ui-conversation/src/client/chat/StatsLine.tsx
@@ -1,12 +1,14 @@
 // Settled-node identity prevents stream-delta updates from rerendering this row.

 import { memo, useMemo } from 'react'
-import type { ConversationSnapshot } from '@deepseek-ai/dsh-client-runtime/client'
+import type {
+  ConversationSnapshot, UseProjection,
+} from '@deepseek-ai/dsh-client-runtime/client'
+import type { ModelRequestTelemetry } from '@deepseek-ai/dsh-client-connection/client'
 import type { SnapshotSelectorHook } from '@deepseek-ai/dsh-client-ui-slots'
+import type { TokenUsageProjection } from '@deepseek-ai/dsh-token-meter/client'
 import css from './StatsLine.module.css'

-type SessionMetrics = NonNullable<ConversationSnapshot['metrics']>
-
 interface VisibleCounts {
  turns: number
  steps: number
@@ -44,59 +46,59 @@ export function formatMetricTokens(value: number): string {

 /**
 * Existing Web cache-hit formula over disjoint uncached and cache-read input.
- * @param metrics - Host-owned durable usage.
+ * @param usage - full-log token usage projection.
 * @returns rounded integer percent, or null when no input was billed.
 */
-export function cacheHitPercent(metrics: SessionMetrics): number | null {
-  const denominator = metrics.uncachedInputTokens + metrics.cacheReadTokens
+export function cacheHitPercent(usage: TokenUsageProjection): number | null {
+  const denominator = usage.uncachedInputTokens + usage.cacheReadTokens
  return denominator === 0
    ? null
-    : Math.round(metrics.cacheReadTokens / denominator * 100)
+    : Math.round(usage.cacheReadTokens / denominator * 100)
 }

 /**
 * Current context occupancy using the TUI's integer rounding and upper clamp.
- * @param metrics - Host-owned durable pressure.
- * @param contextWindow - capacity from the latest request observed on this mux generation.
+ * @param request - one atomic request snapshot observed on this mux generation.
 * @returns occupancy percent, or null when either input is unavailable.
 */
-export function contextPercent(metrics: SessionMetrics, contextWindow: number | undefined): number | null {
-  if (metrics.contextTokens === undefined || contextWindow === undefined) return null
-  return Math.min(100, Math.round(metrics.contextTokens / contextWindow * 100))
+export function contextPercent(request: ModelRequestTelemetry | null): number | null {
+  if (request?.contextTokens === undefined || request.contextWindow === undefined) return null
+  return Math.min(100, Math.round(request.contextTokens / request.contextWindow * 100))
 }

-/** Props: the conversation-snapshot selector hook (handed down by ChatView). */
-export interface StatsLineProps { useSession: SnapshotSelectorHook<ConversationSnapshot> }
+/** Props: standard session hooks handed down by ChatView. */
+export interface StatsLineProps {
+  useSession: SnapshotSelectorHook<ConversationSnapshot>
+  useProjection: UseProjection
+}

-export const StatsLine = memo(function StatsLine({ useSession }: StatsLineProps) {
+export const StatsLine = memo(function StatsLine({ useSession, useProjection }: StatsLineProps) {
  const nodes = useSession(s => s.nodes)
-  const metrics = useSession(s => s.metrics)
-  const contextWindow = useSession(s => s.modelRequestContextWindow)
+  const modelRequest = useSession(s => s.modelRequest)
+  const usage = useProjection('tokenUsage')
  const counts = useMemo(() => deriveVisibleCounts(nodes), [nodes])
-  if (counts.steps === 0 && (
-    metrics === null
-    || (
-      metrics.uncachedInputTokens === 0
-      && metrics.outputTokens === 0
-      && metrics.cacheReadTokens === 0
-      && (metrics.contextTokens ?? 0) === 0
-    )
-  )) return null
+  const hasUsage = usage !== undefined && (
+    usage.uncachedInputTokens !== 0
+    || usage.outputTokens !== 0
+    || usage.cacheReadTokens !== 0
+    || usage.cacheWriteTokens !== 0
+  )
+  const context = contextPercent(modelRequest)
+  if (counts.steps === 0 && !hasUsage && context === null) return null
+
  const parts: string[] = []
-  if (metrics === null) {
+  if (usage === undefined) {
    parts.push('usage unknown')
-    parts.push('context unknown')
  } else {
-    parts.push(`${formatMetricTokens(metrics.uncachedInputTokens)} uncached input`)
-    parts.push(`${formatMetricTokens(metrics.outputTokens)} output`)
-    parts.push(`${formatMetricTokens(metrics.cacheReadTokens)} cache read`)
-    const cacheHit = cacheHitPercent(metrics)
+    parts.push(`${formatMetricTokens(usage.uncachedInputTokens)} uncached input`)
+    parts.push(`${formatMetricTokens(usage.outputTokens)} output`)
+    parts.push(`${formatMetricTokens(usage.cacheReadTokens)} cache read`)
+    const cacheHit = cacheHitPercent(usage)
    if (cacheHit !== null) parts.push(`cache hit ${cacheHit}%`)
-    const context = contextPercent(metrics, contextWindow)
-    parts.push(context === null
-      ? 'context unknown'
-      : `context ${context}% of ${formatMetricTokens(contextWindow as number)}`)
  }
+  parts.push(context === null || modelRequest?.contextWindow === undefined
+    ? 'context unknown'
+    : `context ${context}% of ${formatMetricTokens(modelRequest.contextWindow)}`)
  parts.push(`${counts.turns} turns`)
  parts.push(`${counts.steps} steps`)
  return <div className={css.root}>{parts.join(' · ')}</div>
--- a/packages/client/ui-conversation/tests/chat-branch-tails.spec.tsx
+++ b/packages/client/ui-conversation/tests/chat-branch-tails.spec.tsx
@@ -120,18 +120,20 @@ describe('small branch tails', () => {
  it('StatsLine omits the cache-hit segment when no input accounting exists at all', () => {
    const snap = {
      nodes: [{ kind: 'assistant', seq: 1, turn: 1, step: 1, blocks: [], usage: { outputTokens: 10 } }],
-      metrics: {
-        logRevision: 2,
-        projectionRevision: 0,
-        uncachedInputTokens: 0,
-        outputTokens: 10,
-        cacheReadTokens: 0,
-        cacheWriteTokens: 5_000,
-      },
+      modelRequest: null,
+    }
+    const usage = {
+      uncachedInputTokens: 0,
+      outputTokens: 10,
+      cacheReadTokens: 0,
+      cacheWriteTokens: 5_000,
    }
    const source = { getSnapshot: () => snap, subscribe: () => () => {} }
    const view = render(
-      <StatsLine useSession={bindSnapshotSelector(source) as unknown as StatsLineProps['useSession']} />,
+      <StatsLine
+        useSession={bindSnapshotSelector(source) as unknown as StatsLineProps['useSession']}
+        useProjection={(() => usage)}
+      />,
    )
    expect(view.getByText(
      '0 uncached input · 10 output · 0 cache read · context unknown · 1 turns · 1 steps',
--- a/packages/client/ui-conversation/tests/chat-code-subcalls.spec.tsx
+++ b/packages/client/ui-conversation/tests/chat-code-subcalls.spec.tsx
@@ -58,7 +58,7 @@ function snapshotWith(
    sessionId: SID, nodes, foldDegraded: false, partial: null, runningCalls, codeDispatches,
    pending: [], queue: [], running: runningCalls.length > 0, composerPhase: 'active', removed: false,
    openState: 'open', openError: null,
-    hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null, metrics: null,
+    hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null, modelRequest: null,
  }
 }

--- a/packages/client/ui-conversation/tests/chat-stats-bash-sample.spec.tsx
+++ b/packages/client/ui-conversation/tests/chat-stats-bash-sample.spec.tsx
@@ -1,5 +1,5 @@
 // @vitest-environment jsdom
-// StatsLine (rendered inside the chat view body): durable metrics presentation + the RFC
+// StatsLine (rendered inside the chat view body): projection presentation + the RFC
 // hard acceptance — zero renders during streaming. Bash sample row: the
 // canonical sub-agent differential decided INSIDE the component off the
 // standard useSessions kit (no registry predicates — tool ring dissolved).
@@ -7,8 +7,9 @@
 import { afterEach, describe, expect, it, vi } from 'vitest'
 import { act, cleanup, render } from '@testing-library/react'
 import type {
-  AssistantMessageNode, ConversationSnapshot, SessionId, SessionListState, ToolResultNode,
+  AssistantMessageNode, ConversationSnapshot, SessionId, SessionListState, ToolResultNode, UseProjection,
 } from '@deepseek-ai/dsh-client-runtime/client'
+import type { TokenUsageProjection } from '@deepseek-ai/dsh-token-meter/client'
 import { createSnapshotStore } from '@deepseek-ai/dsh-client-runtime/client'
 import { bindSnapshotSelector } from '@deepseek-ai/dsh-client-web-react'
 import type { ToolRowProps } from '@deepseek-ai/dsh-client-ui-conversation/client'
@@ -31,7 +32,7 @@ function snapshotBase(): ConversationSnapshot {
  return {
    sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
-    hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null, metrics: null,
+    hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null, modelRequest: null,
  }
 }

@@ -53,6 +54,27 @@ function makeSource(init?: Partial<ConversationSnapshot>) {
  }
 }

+function makeProjection(initial?: TokenUsageProjection) {
+  let value = initial
+  const subs = new Set<() => void>()
+  const useValue = bindSnapshotSelector({
+    getSnapshot: () => value,
+    subscribe: (fn: () => void) => {
+      subs.add(fn)
+      return () => subs.delete(fn)
+    },
+  })
+  return {
+    set(next: TokenUsageProjection | undefined) {
+      value = next
+      for (const fn of [...subs]) fn()
+    },
+    useProjection: ((_key: 'tokenUsage', selector?: (usage: TokenUsageProjection | undefined) => unknown,
+      eq?: (left: unknown, right: unknown) => boolean) =>
+      useValue(selector ?? (usage => usage), eq)) as UseProjection,
+  }
+}
+
 describe('stats derivation', () => {
  it('counts visible turns and steps without reading node usage', () => {
    const stats = deriveVisibleCounts([
@@ -74,20 +96,23 @@ describe('stats derivation', () => {
  })

  it('keeps the cache formula disjoint from cache writes and rounds/clamps context like the TUI', () => {
-    const durable = {
-      logRevision: 20,
-      projectionRevision: 2,
+    const usage = {
      uncachedInputTokens: 100,
      outputTokens: 50,
      cacheReadTokens: 900,
      cacheWriteTokens: 50_000,
-      contextTokens: 34_500,
    }
-    expect(cacheHitPercent(durable)).toBe(90)
-    expect(contextPercent(durable, 100_000)).toBe(35)
-    expect(contextPercent({ ...durable, contextTokens: 200_000 }, 100_000)).toBe(100)
-    expect(contextPercent(durable, undefined)).toBeNull()
-    expect(cacheHitPercent({ ...durable, uncachedInputTokens: 0, cacheReadTokens: 0 })).toBeNull()
+    const request = {
+      turn: 1, step: 1, provider: 'p', model: 'm',
+      contextTokens: 34_500, contextWindow: 100_000,
+    }
+    expect(cacheHitPercent(usage)).toBe(90)
+    expect(contextPercent(request)).toBe(35)
+    expect(contextPercent({ ...request, contextTokens: 200_000 })).toBe(100)
+    expect(contextPercent({
+      turn: 1, step: 1, provider: 'p', model: 'm', contextTokens: 34_500,
+    })).toBeNull()
+    expect(cacheHitPercent({ ...usage, uncachedInputTokens: 0, cacheReadTokens: 0 })).toBeNull()
  })

  it('formats large values compactly in the existing en-US style', () => {
@@ -98,25 +123,28 @@ describe('stats derivation', () => {
 })

 describe('StatsLine', () => {
-  function props(source: { getSnapshot(): ConversationSnapshot; subscribe(fn: () => void): () => void }): StatsLineProps {
-    return { useSession: bindSnapshotSelector(source) }
+  function props(
+    source: { getSnapshot(): ConversationSnapshot; subscribe(fn: () => void): () => void },
+    projection = makeProjection(),
+  ): StatsLineProps {
+    return { useSession: bindSnapshotSelector(source), useProjection: projection.useProjection }
  }

  it('renders separate durable counters, cache hit, context occupancy, and visible counts', () => {
    const { source } = makeSource({
      nodes: [assistant(1, 1, { inputTokens: 10, outputTokens: 5, cacheReadTokens: 90 })],
-      metrics: {
-        logRevision: 30,
-        projectionRevision: 4,
-        uncachedInputTokens: 120_237,
-        outputTokens: 13_881,
-        cacheReadTokens: 2_172_544,
-        cacheWriteTokens: 99_999,
-        contextTokens: 89_600,
+      modelRequest: {
+        turn: 1, step: 1, provider: 'p', model: 'm',
+        contextTokens: 89_600, contextWindow: 256_000,
      },
-      modelRequestContextWindow: 256_000,
    })
-    const view = render(<StatsLine {...props(source)} />)
+    const projection = makeProjection({
+      uncachedInputTokens: 120_237,
+      outputTokens: 13_881,
+      cacheReadTokens: 2_172_544,
+      cacheWriteTokens: 99_999,
+    })
+    const view = render(<StatsLine {...props(source, projection)} />)
    expect(view.getByText(
      '120.2k uncached input · 13.9k output · 2.2m cache read · cache hit 95% · context 35% of 256k · 1 turns · 1 steps',
    )).toBeTruthy()
@@ -125,68 +153,80 @@ describe('StatsLine', () => {
    expect(emptyView.container.textContent).toBe('')
  })

-  it('renders durable counters without a percentage before live capacity is observed', () => {
+  it('renders durable counters without a percentage before a complete request snapshot is observed', () => {
    const { source } = makeSource({
      nodes: [assistant(1, 1)],
-      metrics: {
-        logRevision: 4,
-        projectionRevision: 1,
-        uncachedInputTokens: 120,
-        outputTokens: 20,
-        cacheReadTokens: 30,
-        cacheWriteTokens: 10,
+      modelRequest: {
+        turn: 1, step: 1, provider: 'p', model: 'm',
        contextTokens: 8_000,
      },
    })
-    const view = render(<StatsLine {...props(source)} />)
+    const projection = makeProjection({
+      uncachedInputTokens: 120,
+      outputTokens: 20,
+      cacheReadTokens: 30,
+      cacheWriteTokens: 10,
+    })
+    const view = render(<StatsLine {...props(source, projection)} />)
    expect(view.getByText(
      '120 uncached input · 20 output · 30 cache read · cache hit 20% · context unknown · 1 turns · 1 steps',
    )).toBeTruthy()
    expect(view.container.textContent).not.toContain('% of')
  })

-  it('renders honest unknowns when the host projection is missing', () => {
+  it('renders honest unknowns when the tokenUsage key and request snapshot are missing', () => {
    const { source } = makeSource({ nodes: [assistant(1, 1)] })
    const view = render(<StatsLine {...props(source)} />)
    expect(view.getByText('usage unknown · context unknown · 1 turns · 1 steps')).toBeTruthy()
  })

  it.each([
-    { uncachedInputTokens: 1, outputTokens: 0, cacheReadTokens: 0, contextTokens: 0 },
-    { uncachedInputTokens: 0, outputTokens: 1, cacheReadTokens: 0, contextTokens: 0 },
-    { uncachedInputTokens: 0, outputTokens: 0, cacheReadTokens: 1, contextTokens: 0 },
-    { uncachedInputTokens: 0, outputTokens: 0, cacheReadTokens: 0, contextTokens: 1 },
-  ])('keeps a metrics-only row visible for each nonzero projection bucket', (nonzero) => {
-    const { source } = makeSource({
-      metrics: {
-        logRevision: 1,
-        projectionRevision: 0,
-        cacheWriteTokens: 0,
-        ...nonzero,
+    { uncachedInputTokens: 1, outputTokens: 0, cacheReadTokens: 0, cacheWriteTokens: 0 },
+    { uncachedInputTokens: 0, outputTokens: 1, cacheReadTokens: 0, cacheWriteTokens: 0 },
+    { uncachedInputTokens: 0, outputTokens: 0, cacheReadTokens: 1, cacheWriteTokens: 0 },
+    { uncachedInputTokens: 0, outputTokens: 0, cacheReadTokens: 0, cacheWriteTokens: 1 },
+  ])('keeps a usage-only row visible for each nonzero projection bucket', (usage) => {
+    const { source } = makeSource()
+    const view = render(<StatsLine {...props(source, makeProjection(usage))} />)
+    expect(view.container.textContent).toContain('0 turns · 0 steps')
+  })
+
+  it('keeps a context-only row visible and hides an all-zero empty session', () => {
+    const context = makeSource({
+      modelRequest: {
+        turn: 1, step: 1, provider: 'p', model: 'm',
+        contextTokens: 1, contextWindow: 10,
      },
    })
-    const view = render(<StatsLine {...props(source)} />)
-    expect(view.container.textContent).toContain('0 turns · 0 steps')
+    expect(render(
+      <StatsLine {...props(context.source, makeProjection({
+        uncachedInputTokens: 0, outputTokens: 0, cacheReadTokens: 0, cacheWriteTokens: 0,
+      }))} />,
+    ).container.textContent).toContain('context 10% of 10')
+    const empty = makeSource()
+    expect(render(
+      <StatsLine {...props(empty.source, makeProjection({
+        uncachedInputTokens: 0, outputTokens: 0, cacheReadTokens: 0, cacheWriteTokens: 0,
+      }))} />,
+    ).container.textContent).toBe('')
  })

  it('renders ZERO times during streaming chunk frames (RFC hard acceptance)', () => {
    const { set, source } = makeSource({
      nodes: [assistant(1, 1)],
-      metrics: {
-        logRevision: 4,
-        projectionRevision: 0,
-        uncachedInputTokens: 1,
-        outputTokens: 1,
-        cacheReadTokens: 0,
-        cacheWriteTokens: 0,
-      },
+    })
+    const projection = makeProjection({
+      uncachedInputTokens: 1,
+      outputTokens: 1,
+      cacheReadTokens: 0,
+      cacheWriteTokens: 0,
    })
    let renders = 0
    function Counting(p: StatsLineProps) {
      renders += 1
      return <StatsLine {...p} />
    }
-    render(<Counting {...props(source)} />)
+    render(<Counting {...props(source, projection)} />)
    const before = renders
    // Chunk frames swap partial only; nodes keeps its reference (object-layer contract).
    act(() => { set({ partial: { turn: 1, step: 2, blocks: [{ kind: 'text', text: 'a' }] } }) })
@@ -194,6 +234,28 @@ describe('StatsLine', () => {
    act(() => { set({ running: true }) })
    expect(renders).toBe(before)
  })
+
+  it('updates for a new usage projection or atomic request snapshot', () => {
+    const { set, source } = makeSource({ nodes: [assistant(1, 1)] })
+    const projection = makeProjection()
+    const view = render(<StatsLine {...props(source, projection)} />)
+    expect(view.container.textContent).toContain('usage unknown · context unknown')
+    act(() => {
+      projection.set({
+        uncachedInputTokens: 7, outputTokens: 2, cacheReadTokens: 1, cacheWriteTokens: 0,
+      })
+    })
+    expect(view.container.textContent).toContain('7 uncached input · 2 output · 1 cache read')
+    act(() => {
+      set({
+        modelRequest: {
+          turn: 1, step: 2, provider: 'p', model: 'm',
+          contextTokens: 75, contextWindow: 100,
+        },
+      })
+    })
+    expect(view.container.textContent).toContain('context 75% of 100')
+  })
 })

 describe('bash sample row', () => {
--- a/packages/client/ui-conversation/tests/chat-view.spec.tsx
+++ b/packages/client/ui-conversation/tests/chat-view.spec.tsx
@@ -31,7 +31,7 @@ function snapshotBase(): ConversationSnapshot {
  return {
    sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
-    hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null, metrics: null,
+    hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null, modelRequest: null,
  }
 }

--- a/packages/client/ui-conversation/tests/gate-branch-tails.spec.tsx
+++ b/packages/client/ui-conversation/tests/gate-branch-tails.spec.tsx
@@ -20,7 +20,7 @@ function snapshotBase(): ConversationSnapshot {
  return {
    sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false, openState: 'open', openError: null,
-    hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null, metrics: null,
+    hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null, modelRequest: null,
  }
 }

@@ -36,7 +36,7 @@ describe('render branch tails', () => {
    expect(view.container.querySelector('[data-state="ok"]')).not.toBeNull()
  })

-  it('StatsLine takes durable counters from metrics while keeping visible node counts', () => {
+  it('StatsLine takes durable counters from tokenUsage while keeping visible node counts', () => {
    const snap = {
      nodes: [
        { kind: 'assistant', seq: 1, turn: 1, step: 1, blocks: [] },
@@ -44,18 +44,20 @@ describe('render branch tails', () => {
        // outputTokens absent: the tokens sum's ?? 0 arm for output.
        { kind: 'assistant', seq: 3, turn: 2, step: 1, blocks: [], usage: { inputTokens: 5 } },
      ],
-      metrics: {
-        logRevision: 9,
-        projectionRevision: 1,
-        uncachedInputTokens: 9,
-        outputTokens: 6,
-        cacheReadTokens: 0,
-        cacheWriteTokens: 0,
-      },
+      modelRequest: null,
+    }
+    const usage = {
+      uncachedInputTokens: 9,
+      outputTokens: 6,
+      cacheReadTokens: 0,
+      cacheWriteTokens: 0,
    }
    const source = { getSnapshot: () => snap, subscribe: () => () => {} }
    const view = render(
-      <StatsLine useSession={bindSnapshotSelector(source) as unknown as UseSession<ConversationSnapshot>} />,
+      <StatsLine
+        useSession={bindSnapshotSelector(source) as unknown as UseSession<ConversationSnapshot>}
+        useProjection={(() => usage)}
+      />,
    )
    expect(view.getByText(
      '9 uncached input · 6 output · 0 cache read · cache hit 0% · context unknown · 2 turns · 3 steps',
--- a/packages/client/ui-conversation/tests/input-bar.spec.tsx
+++ b/packages/client/ui-conversation/tests/input-bar.spec.tsx
@@ -23,7 +23,7 @@ function snapshotOf(overrides: Partial<ConversationSnapshot> = {}): Conversation
    sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
    openState: 'open', openError: null, hasMore: false, loadingOlder: false,
-    promptError: null, blank: false, lastAgentError: null, metrics: null,
+    promptError: null, blank: false, lastAgentError: null, modelRequest: null,
    ...overrides,
  }
 }
--- a/packages/client/ui-conversation/tests/input-matrix.spec.tsx
+++ b/packages/client/ui-conversation/tests/input-matrix.spec.tsx
@@ -26,7 +26,7 @@ function mountBar(shell: SessionInputShell, over?: { running?: boolean; disabled
    sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: over?.running ?? false, composerPhase: 'active',
    removed: over?.disabled ?? false, openState: 'open', openError: null, hasMore: false,
-    loadingOlder: false, promptError: null, blank: false, lastAgentError: null, metrics: null,
+    loadingOlder: false, promptError: null, blank: false, lastAgentError: null, modelRequest: null,
  })
  const props: InputBarProps = {
    sessionId: SID,
--- a/packages/client/ui-conversation/tests/input-scenarios.spec.tsx
+++ b/packages/client/ui-conversation/tests/input-scenarios.spec.tsx
@@ -112,7 +112,7 @@ async function scopedBench(register?: (slash: SlashService) => void) {
    sessionId, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
    openState: 'open', openError: null, hasMore: false, loadingOlder: false,
-    promptError: null, blank: false, lastAgentError: null, metrics: null,
+    promptError: null, blank: false, lastAgentError: null, modelRequest: null,
  })
  const barProps: InputBarProps = {
    sessionId,
--- a/packages/client/ui-conversation/tests/queue-dock.spec.tsx
+++ b/packages/client/ui-conversation/tests/queue-dock.spec.tsx
@@ -20,7 +20,7 @@ function snapshotWith(queue: QueuedMessage[]): ConversationSnapshot {
  return {
    sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue, running: true, composerPhase: 'active', removed: false, openState: 'open', openError: null,
-    hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null, metrics: null,
+    hasMore: false, loadingOlder: false, promptError: null, blank: false, lastAgentError: null, modelRequest: null,
  }
 }

--- a/packages/client/ui-conversation/tests/skeleton.spec.tsx
+++ b/packages/client/ui-conversation/tests/skeleton.spec.tsx
@@ -50,7 +50,7 @@ function conversationSnapshot(overrides: Partial<ConversationSnapshot> = {}): Co
    sessionId: SID, nodes: [], foldDegraded: false, partial: null, runningCalls: [], codeDispatches: new Map(),
    pending: [], queue: [], running: false, composerPhase: 'active', removed: false,
    openState: 'open', openError: null, hasMore: false, loadingOlder: false,
-    promptError: null, blank: false, lastAgentError: null, metrics: null,
+    promptError: null, blank: false, lastAgentError: null, modelRequest: null,
    ...overrides,
  }
 }
--- a/packages/client/ui-conversation/tsconfig.json
+++ b/packages/client/ui-conversation/tsconfig.json
@@ -26,6 +26,9 @@
    {
      "path": "../../session-projection/session-projection"
    },
+    {
+      "path": "../../llm/token-meter"
+    },
    {
      "path": "../../plan/plan-mode"
    },