feat(tool-fs): result-time applied-hunk diffs for write/edit
fs write/edit now emit a result-time contextual-diff tool_call_update
(the applied hunk with ±3 context lines, one hunk per replace_all site),
matching what claude-agent-acp sends and what makes an editor render the
change in place. The call-time snippet diff stays; the result hunk
supersedes it (ACP content-replace).
Mechanism:
- A persisted tool-private `meta` channel: execute may return
`{ content, meta }`; `meta` (JsonValue) rides on the tool/result event
and is handed back to presentResult, so the diff reproduces on replay
(event-sourced). JsonValue is now exported from dsh-session.
- The backend returns raw before/after text (storage facts) on
FsWriteOutcome/FsEditOutcome; the tool computes the hunk via the npm
`diff` package's structuredPatch. A create has no before → no result
diff; a failed/aborted mutation carries no meta.
- ToolResultView gains a DiffResultView; the bridge's result-side switch
renders it as {type:'diff'} content blocks.
RFC: docs/rfc/implemented/architecture/2026-07-02-result-time-applied-hunk-diffs.md
(justifies the npm `diff` runtime dep over vendoring and the meta channel);
the render-intent-union RFC's Non-goal is updated to record this shipped.
All fs snapshot goldens re-recorded; edit/overwrite gain the contextual
result diff, create/read/policy-reject unchanged in structure.
This commit is contained in:
Tianyi Cui
@@ -724,6 +724,9 @@ async function runStep(
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content: result.content,
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isError: result.isError,
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...result.error ? { error: result.error } : {},
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// The tool's private presentation payload (e.g. a result-time diff),
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// persisted so a UI bridge reproduces the card on replay.
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...result.meta !== undefined ? { meta: result.meta } : {},
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}, { surfaceOp: 'append', sourceEventSeqs: [callEvent.seq] })
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// signal CAN flip during the await above (abort() inside a tool);
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// the analyzer can't see through the await boundary.
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@@ -110,6 +110,32 @@ describe('agent loop', () => {
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expect(types).toContain('tool/result')
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})
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it('threads a tool-attached meta (execute object return) onto the tool/result event', async () => {
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const adapter = new MockAdapter([
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toolCallResponse('c1', 'writer', { path: 'a.txt' }, 'writing'),
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textResponse('done'),
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])
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const ctx = await harness(adapter)
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// A tool that returns the { content, meta } object form: the loop must
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// persist `meta` on the tool/result event so a UI reproduces the card on replay.
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ctx.tools.register(defineTool({
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name: 'writer',
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description: 'writes a file',
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parameters: { path: { type: 'string' } },
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async execute() {
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return { content: [{ type: 'text', text: 'ok' }], meta: { diffs: [{ path: 'a.txt', oldText: null, newText: 'x' }] } }
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},
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}))
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const agent = ctx.agentLoop.create(AgentId('a1'), { model: 'mock' })
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send(agent, 'use the tool')
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await waitForIdle(ctx, agent)
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const toolResult = agent.session.events.find(e => e.type === 'tool/result')
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expect(toolResult?.type === 'tool/result' && toolResult.data.meta)
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.toEqual({ diffs: [{ path: 'a.txt', oldText: null, newText: 'x' }] })
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})
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it('passes assembled system prompt and tool schemas into the request', async () => {
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const adapter = new MockAdapter([textResponse('ok')])
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const ctx = await harness(adapter)
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@@ -16,6 +16,7 @@ import { SurfaceManager, isSurfaceEligibleType } from './surface.ts'
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export * from './types.ts'
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export { isJsonValue } from './json.ts'
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export type { JsonValue } from './json.ts'
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export { interruptedTurnClosers } from './repair.ts'
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export type { SurfaceNode } from './surface.ts'
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export { isSurfaceEvent, isSurfaceEligibleType } from './surface.ts'
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@@ -13,6 +13,16 @@
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* @module @deepseek-ai/dsh-session/json
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*/
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/**
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* A value that round-trips losslessly through JSON: `null`, a boolean, a finite
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* number, a string, an array of such values, or a plain object whose values are
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* such values. The static type companion to {@link isJsonValue} (which validates
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* the same shape at runtime). Use it to type a payload that must survive
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* session-log persistence and replay byte-identically — e.g. a tool's private
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* presentation `meta`.
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*/
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export type JsonValue = null | boolean | number | string | JsonValue[] | { [key: string]: JsonValue }
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/**
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* Whether `value` is losslessly JSON-serializable: only `null`, finite numbers,
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* booleans, strings, plain arrays, and plain objects of such values. Rejects
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@@ -1,5 +1,6 @@
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import type { Branded } from '@deepseek-ai/dsh-brand'
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import type { CallId, ContentBlock, MessageSource, StreamChunk, TokenUsage } from '@deepseek-ai/dsh-llm'
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import type { JsonValue } from './json.ts'
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/** Identifies one session in the store (and its persistence artifacts). */
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export type SessionId = Branded<'SessionId'>
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@@ -210,7 +211,16 @@ export interface SessionEventMap {
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*/
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'assistant/message': { turn: number; step: number; content: ContentBlock[]; usage?: TokenUsage }
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'tool/call': { turn: number; step: number; callId: CallId; name: string; arguments: string }
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'tool/result': { turn: number; step: number; callId: CallId; content: ContentBlock[]; isError: boolean; error?: { name: string; code: string } }
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/**
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* A completed tool call's model-facing result, plus an optional tool-private
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* `meta` presentation payload. `meta` is opaque to the core — the producing
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* tool owns its shape and reads it back in `presentResult` — and is a
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* {@link JsonValue} so it persists in the durable log and reproduces on replay
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* (a UI bridge renders the identical card from a loaded session). Absent unless
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* the tool attaches one (e.g. `dsh-tool-fs` carries its result-time contextual
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* diff here).
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*/
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'tool/result': { turn: number; step: number; callId: CallId; content: ContentBlock[]; isError: boolean; error?: { name: string; code: string }; meta?: JsonValue }
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/** Steering content injected between steps of a running turn. */
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'steering/message': { turn: number; content: ContentBlock[]; source: MessageSource }
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/**
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@@ -24,7 +24,7 @@ Tool registry and execution waterfall. Tool plugins register their schemas and e
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### Key types
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- `ToolDefinition` — `ToolSchema` + `execute(args, exec): Promise<ContentBlock[]>`, plus optional `presentCall(args)` / `presentResult(args, result)` for tool-owned UI presentation (see below).
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- `ToolDefinition` — `ToolSchema` + `execute(args, exec): Promise<ContentBlock[] | { content: ContentBlock[]; meta? }>` (the bare array is the model-facing content; the object form additionally attaches an opaque, JSON-serializable `meta` presentation payload persisted on the `tool/result` event and handed back to `presentResult`), plus optional `presentCall(args)` / `presentResult(args, result)` for tool-owned UI presentation (see below).
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- `ToolExecution` — one pending tool call: `{ callId, name, arguments, agent?, signal? }`.
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- `ToolExecutionResult` — outcome: `{ callId, content, isError, error? }`. On failure with a `HarnessError`, `error: { name, code }` carries the structured failure class alongside the model-facing text (the loop forwards it onto the `tool/result` session event for retry/sandbox plugins and replay).
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- `ToolCallView` / `ToolResultView` — provider-neutral `card`-tagged render intents a tool returns from `presentCall` / `presentResult` to own how a UI renders ITS calls (see "Tool-owned UI presentation").
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@@ -76,11 +76,12 @@ A tool owns how ITS calls render in a UI (an editor's tool-call card, a CLI log
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- `{ card: 'generic', title, kind?, rawInput?, content?, locations? }` — the default card: a human-readable `title`, an optional `kind` (`read`/`edit`/`execute`/… for icon/treatment, default `other`), an optional `rawInput` (the salient input to show in a detail view — e.g. a background task id, NOT the whole args object), optional `content` (extra UI content blocks), and optional `locations` (`{ path, line? }[]` — files this call reads/modifies, so a capable UI can follow along; the ACP bridge forwards them as `tool_call.locations`).
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- `{ card: 'terminal', title, description?, cwd? }` — a shell command: a capable UI renders a terminal card (the `title` is the command, `description` renders above it, `cwd` heads it); an incapable UI falls back to a generic execute card.
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- `{ card: 'diff', title, diffs, locations? }` — a file create/modify: a capable UI renders an inline diff card from `diffs` (`{ path, oldText, newText }[]`; `oldText: null` for a new file). Used by `write`/`edit`.
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- `presentResult(args, result): ToolResultView | undefined` — the COMPLETED state, given the same `args` and the `{ content, isError }` result, one of:
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- `presentResult(args, result): ToolResultView | undefined` — the COMPLETED state, given the same `args` and the `{ content, isError, meta? }` result, one of:
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- `{ card: 'generic', title?, content? }` — an optional replacement `title` and reformatted `content`.
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- `{ card: 'terminal', title?, output?, exitCode?, signal? }` — a terminal run's captured `output` and exit status. A capable UI shows an exit-status pill; an incapable UI gets a fenced ` ```console ` fallback the BRIDGE derives from `output` (the tool does not encode the fences).
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- `{ card: 'diff', title?, diffs }` — a completed file mutation as an inline diff. `diffs` is `FileDiff[]` — the APPLIED hunks with surrounding context (one entry per changed site), computed from the before/after file content, distinct from the call-time whole-snippet `diff`. Used by `write`/`edit`; a `tool_call_update.content` replaces the call's content, so this supersedes the pending snippet.
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Returning `undefined` (or omitting a method) tells a UI to fall back to a generic presentation (title = tool name, raw args as input, raw result content). Both methods must be **pure and side-effect-free**: a UI may call them during live streaming AND during a session-log replay, so they depend only on their arguments. With `defineTool`, `args` is the typed `InferArgs<S>` shape; the helper soft-validates before calling (a malformed/older logged arg shape yields `undefined` rather than throwing, since display must never crash a replay). The views are provider-neutral — the ACP bridge (`dsh-acp`) maps each `card` to ACP `tool_call`/`tool_call_update` wire fields (a `diff` card to a `{ type: 'diff' }` content block, a `terminal` card to the `_meta` terminal convention), and relativizes a file card's title against the session cwd. See the render-intent-union RFC (`docs/rfc/implemented/architecture/2026-07-02-tool-render-intent-union.md`); `dsh-tool-bash` (terminal) and `dsh-tool-fs` (diff/generic) are the reference implementations.
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Returning `undefined` (or omitting a method) tells a UI to fall back to a generic presentation (title = tool name, raw args as input, raw result content). Both methods must be **pure and side-effect-free**: a UI may call them during live streaming AND during a session-log replay, so they depend only on their arguments. `result.meta` is the tool's own optional presentation payload (`JsonValue`), attached by `execute` (see below) and persisted on the `tool/result` event, so a `presentResult` reading it stays replay-deterministic (the same `meta` is read back from the log). With `defineTool`, `args` is the typed `InferArgs<S>` shape; the helper soft-validates before calling (a malformed/older logged arg shape yields `undefined` rather than throwing, since display must never crash a replay). The views are provider-neutral — the ACP bridge (`dsh-acp`) maps each `card` to ACP `tool_call`/`tool_call_update` wire fields (a `diff` card to a `{ type: 'diff' }` content block, a `terminal` card to the `_meta` terminal convention), and relativizes a file card's title against the session cwd. See the render-intent-union RFC (`docs/rfc/implemented/architecture/2026-07-02-tool-render-intent-union.md`) and the applied-hunk-diffs RFC (`docs/rfc/implemented/architecture/2026-07-02-result-time-applied-hunk-diffs.md`); `dsh-tool-bash` (terminal) and `dsh-tool-fs` (diff/generic) are the reference implementations.
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```ts
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import { defineTool } from '@deepseek-ai/dsh-tools'
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@@ -24,12 +24,14 @@
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"peerDependencies": {
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"@deepseek-ai/dsh-agent": "^0.0.1",
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"@deepseek-ai/dsh-llm": "^0.0.1",
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"@deepseek-ai/dsh-session": "^0.0.1",
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"@deepseek-ai/dsh-system-prompt": "^0.0.1",
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"cordis": "^4.0.0-rc.6"
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},
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"devDependencies": {
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"@deepseek-ai/dsh-agent": "workspace:^",
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"@deepseek-ai/dsh-llm": "workspace:^",
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"@deepseek-ai/dsh-session": "workspace:^",
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"@deepseek-ai/dsh-system-prompt": "workspace:^",
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"cordis": "^4.0.0-rc.6"
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}
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@@ -11,6 +11,7 @@ import { Context, Service } from 'cordis'
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import type { CallId, ContentBlock, ToolSchema } from '@deepseek-ai/dsh-llm'
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import { HarnessError } from '@deepseek-ai/dsh-llm'
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import type { Agent } from '@deepseek-ai/dsh-agent'
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import type { JsonValue } from '@deepseek-ai/dsh-session'
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import type {} from '@deepseek-ai/dsh-system-prompt'
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export {
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@@ -87,6 +88,13 @@ export interface FileDiff {
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oldText: string | null
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/** Content after the change. */
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newText: string
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/**
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* Index signature so a `FileDiff` is a valid {@link JsonValue} member — a tool
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* persists result-time diffs as `tool/result` `meta`, which must round-trip
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* through the session log. Every declared field is already JSON-compatible;
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* this only makes the structural compatibility explicit.
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*/
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[key: string]: string | null
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}
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/**
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@@ -159,7 +167,8 @@ export interface TerminalCallView {
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* A call that creates or modifies files, rendered as an inline diff card by a
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* capable UI. Set by a tool whose call writes/edits a file (e.g. `write`,
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* `edit`). The diffs are derived from the call ARGUMENTS (a create's `oldText` is
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* `null`); result-time applied-hunk diffs are a separate follow-up.
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* `null`); the result-time applied-hunk diff (with context) is a separate
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* {@link DiffResultView} the tool emits after `execute`.
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*/
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export interface DiffCallView {
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card: 'diff'
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@@ -179,7 +188,7 @@ export interface DiffCallView {
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* {@link ToolDefinition.presentResult}; omitting the method keeps the pending
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* title and renders the raw result content.
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*/
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export type ToolResultView = GenericResultView | TerminalResultView
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export type ToolResultView = GenericResultView | TerminalResultView | DiffResultView
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/**
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* The default completed card: an optional replacement title and reformatted
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@@ -217,9 +226,37 @@ export interface TerminalResultView {
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signal?: string
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}
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/**
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* A completed file mutation rendered as an inline diff card, the *result-time*
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* analogue of {@link DiffCallView}. Set by a tool whose `execute` applied a
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* file change (e.g. `write`, `edit`): `diffs` are the APPLIED hunks computed
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* from the before/after file content (one entry per hunk, each with surrounding
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* context lines), so the editor shows the real change with context — distinct
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* from the call-time whole-snippet {@link DiffCallView}. A `tool_call_update`'s
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* content REPLACES the call's content in an editor, so this result diff
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* supersedes the pending snippet.
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*/
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export interface DiffResultView {
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card: 'diff'
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/** Replacement title for the completed call. Omit to keep the pending-state title. */
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title?: string
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/** One entry per applied hunk (a contextual diff), in file order. */
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diffs: FileDiff[]
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}
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/**
|
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* What a tool's `execute` returns. The bare {@link ContentBlock}`[]` form is the
|
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* common case (model-facing content only); the object form additionally attaches
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* a tool-private `meta` presentation payload ({@link JsonValue}) that the
|
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* registry threads onto the `tool/result` session event and hands back to the
|
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* tool's `presentResult`. `meta` is opaque to the core — the tool owns its shape
|
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* and validates it on the way out — and persists so replay reproduces the card.
|
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*/
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export type ToolExecuteReturn = ContentBlock[] | { content: ContentBlock[]; meta?: JsonValue }
|
||||
|
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/** A registered tool: its schema plus the execution function. */
|
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export interface ToolDefinition extends ToolSchema {
|
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execute(args: unknown, exec: ToolExecution): Promise<ContentBlock[]>
|
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execute(args: unknown, exec: ToolExecution): Promise<ToolExecuteReturn>
|
||||
/**
|
||||
* Optional: how to present the PENDING state of one call in a UI, derived from
|
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* the call's `args` (parsed arguments, `unknown` — the tool validates/narrows
|
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@@ -246,6 +283,13 @@ export interface ToolResult {
|
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content: ContentBlock[]
|
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/** Whether the call failed. */
|
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isError: boolean
|
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/**
|
||||
* The tool-private presentation payload the tool attached from `execute` (via
|
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* the object return form), threaded verbatim from the `tool/result` event.
|
||||
* Opaque {@link JsonValue}; the tool narrows it back to its own shape. Absent
|
||||
* when the tool attached none.
|
||||
*/
|
||||
meta?: JsonValue
|
||||
}
|
||||
|
||||
/** One pending tool call, as it flows through the execution waterfall. */
|
||||
@@ -289,6 +333,13 @@ export interface ToolExecutionResult {
|
||||
* text in `content` is always present; this is extra structure for code.
|
||||
*/
|
||||
error?: ToolErrorInfo
|
||||
/**
|
||||
* The tool-private presentation payload from a successful `execute` (the object
|
||||
* return form). Threaded onto the `tool/result` session event and back into
|
||||
* {@link ToolResult} for `presentResult`. Opaque {@link JsonValue}; absent when
|
||||
* the tool attached none or the call failed.
|
||||
*/
|
||||
meta?: JsonValue
|
||||
}
|
||||
|
||||
/**
|
||||
@@ -393,8 +444,13 @@ export class ToolRegistry extends Service {
|
||||
// Unknown tool routes through the same catch as a tool-thrown error, so
|
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// both failure classes get structured `{ name, code }` from one path.
|
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if (!tool) throw new ToolNotFoundError(exec.name)
|
||||
const content = await tool.execute(exec.arguments, exec)
|
||||
return { callId: exec.callId, content, isError: false }
|
||||
// Normalize the two `execute` return shapes: a bare ContentBlock[] (no
|
||||
// meta) or a { content, meta } object (a tool attaching a private
|
||||
// presentation payload). An array IS the content; the object carries it.
|
||||
const returned = await tool.execute(exec.arguments, exec)
|
||||
const content = Array.isArray(returned) ? returned : returned.content
|
||||
const meta = Array.isArray(returned) ? undefined : returned.meta
|
||||
return { callId: exec.callId, content, isError: false, ...meta !== undefined ? { meta } : {} }
|
||||
} catch (error: unknown) {
|
||||
return toolErrorResult(exec.callId, error)
|
||||
}
|
||||
|
||||
@@ -19,9 +19,8 @@
|
||||
* @module dsh-tools/schema
|
||||
*/
|
||||
|
||||
import type { ContentBlock } from '@deepseek-ai/dsh-llm'
|
||||
import { assertNever, HarnessError } from '@deepseek-ai/dsh-llm'
|
||||
import type { ToolCallView, ToolDefinition, ToolExecution, ToolResult, ToolResultView } from './index.ts'
|
||||
import type { ToolCallView, ToolDefinition, ToolExecuteReturn, ToolExecution, ToolResult, ToolResultView } from './index.ts'
|
||||
|
||||
// ---------------------------------------------------------------------------
|
||||
// SchemaSpec — the author-facing per-property type
|
||||
@@ -291,9 +290,11 @@ export interface DefineToolOptions<S extends SchemaSpec> {
|
||||
parameters: S
|
||||
/**
|
||||
* Tool execution function. `args` is typed as {@link InferArgs<S>} — zero
|
||||
* casts needed.
|
||||
* casts needed. Returns either a bare {@link ContentBlock}`[]` (model-facing
|
||||
* content only) or a `{ content, meta }` object to also attach a tool-private
|
||||
* presentation payload (see {@link ToolExecuteReturn}).
|
||||
*/
|
||||
execute(args: InferArgs<S>, exec: ToolExecution): Promise<ContentBlock[]>
|
||||
execute(args: InferArgs<S>, exec: ToolExecution): Promise<ToolExecuteReturn>
|
||||
/**
|
||||
* Optional: how to present the PENDING state of one call in a UI (an editor
|
||||
* tool-call card, a CLI log line). `args` is the typed, schema-validated
|
||||
@@ -354,7 +355,7 @@ export function defineTool<S extends SchemaSpec>(options: DefineToolOptions<S>):
|
||||
description: options.description,
|
||||
parameters: schemaSpecToJsonSchema(options.parameters) as unknown as Record<string, unknown>,
|
||||
...options.strict !== undefined ? { strict: options.strict } : {},
|
||||
async execute(args: unknown, exec: ToolExecution): Promise<ContentBlock[]> {
|
||||
async execute(args: unknown, exec: ToolExecution): Promise<ToolExecuteReturn> {
|
||||
// Validate the model-generated args before the typed body runs. On
|
||||
// mismatch we throw ToolArgsError; the registry turns it into an
|
||||
// isError result so the model can self-correct. After this guard, the
|
||||
|
||||
@@ -81,6 +81,38 @@ describe('ToolRegistry', () => {
|
||||
expect(result).toEqual({ callId: CallId('c1'), content: [{ type: 'text', text: 'hi' }], isError: false })
|
||||
})
|
||||
|
||||
it('threads a tool-attached meta (object return form) onto the result', async () => {
|
||||
const ctx = await setup()
|
||||
ctx.tools.register({
|
||||
...echoTool,
|
||||
name: 'meta-tool',
|
||||
async execute() {
|
||||
return { content: [{ type: 'text', text: 'ok' }], meta: { diffs: [{ path: 'a', oldText: null, newText: 'x' }] } }
|
||||
},
|
||||
})
|
||||
const result = await ctx.tools.execute({ callId: CallId('c1'), name: 'meta-tool', arguments: {} })
|
||||
expect(result).toEqual({
|
||||
callId: CallId('c1'),
|
||||
content: [{ type: 'text', text: 'ok' }],
|
||||
isError: false,
|
||||
meta: { diffs: [{ path: 'a', oldText: null, newText: 'x' }] },
|
||||
})
|
||||
})
|
||||
|
||||
it('omits meta when the object return form supplies none', async () => {
|
||||
const ctx = await setup()
|
||||
ctx.tools.register({
|
||||
...echoTool,
|
||||
name: 'no-meta-tool',
|
||||
async execute() {
|
||||
return { content: [{ type: 'text', text: 'ok' }] }
|
||||
},
|
||||
})
|
||||
const result = await ctx.tools.execute({ callId: CallId('c1'), name: 'no-meta-tool', arguments: {} })
|
||||
expect(result).toEqual({ callId: CallId('c1'), content: [{ type: 'text', text: 'ok' }], isError: false })
|
||||
expect('meta' in result).toBe(false)
|
||||
})
|
||||
|
||||
it('returns isError results for unknown tools and throwing tools', async () => {
|
||||
const ctx = await setup()
|
||||
ctx.tools.register({
|
||||
|
||||
Reference in New Issue
Block a user