Merge branch 'worktree/agent-execution-context-rfc' into worktree/explicit-turn-signal

packages/core/agent-loop/src/agent.ts

@@ -8,7 +8,7 @@
 
 import type { Context } from 'cordis'
 import { agentEvents, normalizeAgentCancelCause } from '@deepseek-ai/dsh-agent'
-import type { AgentCancelCause, AgentId, AgentOptions, AgentStatus, SendOptions } from '@deepseek-ai/dsh-agent'
+import type { AgentCancelCause, AgentId, AgentOptions, AgentStatus, InjectOptions, SendOptions } from '@deepseek-ai/dsh-agent'
 import type { Agent } from '@deepseek-ai/dsh-agent'
 import { deepFreeze } from '@deepseek-ai/dsh-llm'
 import type { ContentBlock, MessageSource } from '@deepseek-ai/dsh-llm'
@@ -223,14 +223,20 @@ export class ReactLoopAgent implements Agent {
     agentEvents(this.loopCtx, this).emit('agent/queued', accepted.content, info)
   }
 
-  inject(content: ContentBlock[], options?: SendOptions): void {
+  inject(content: ContentBlock[], options?: InjectOptions): void {
     this.assertNotDisposed()
     const source = this.resolveSource(options)
+    const context = {
+      content,
+      source,
+      ...options?.envelope !== undefined ? { envelope: options.envelope } : {},
+      ...options?.meta !== undefined ? { meta: options.meta } : {},
+    }
     if (isTurnOpen(this.session)) {
       // A turn is open in the LOG (decided from the log, not agent status —
       // status can be `running` with no turn open): the context/message is
       // turn-enclosed by that turn, so append it directly.
-      this.session.append('context/message', { content, source }, { surfaceOp: 'append' })
+      this.session.append('context/message', context, { surfaceOp: 'append' })
       return
     }
     // No turn open: wrap the injection in a one-shot turn so every event stays
@@ -242,7 +248,7 @@ export class ReactLoopAgent implements Agent {
     // are contained by Session and cannot create a false append failure.
     try {
       this.session.append('turn/start', { turn, trigger: { kind: 'injection', source } })
-      this.session.append('context/message', { content, source }, { surfaceOp: 'append' })
+      this.session.append('context/message', context, { surfaceOp: 'append' })
     } finally {
       // Close the turn if turn/start made it into the log. A pre-commit veto
       // must escape rather than being mistaken for a committed turn/end.

packages/core/agent-loop/src/index.ts

@@ -340,6 +340,7 @@ export class AgentLoop extends Service implements AgentFactory {
   static Config = z.object({
     agents: z.array(z.object({
       id: z.string().required(),
+      provider: z.string(),
       model: z.string(),
       cwd: z.string(),
       resumeSessionId: z.string(),
@@ -356,6 +357,7 @@ export class AgentLoop extends Service implements AgentFactory {
     this.runtime = { ctx }
     ctx.effect(() => () => this.ownership.dispose(), 'agentLoop.transactions()')
     ctx.effect(() => ctx.agents.setFactory(this), 'agentLoop.setFactory()')
+    ctx.systemPrompt.variable('provider', context => context.agent?.options.provider)
     ctx.systemPrompt.variable('model', context => context.agent?.options.model)
     ctx.systemPrompt.variable('cwd', context => context.agent?.session.header.cwd)
 

packages/core/agent-loop/src/loop.ts

@@ -6,7 +6,8 @@
  */
 
 import type { Context } from 'cordis'
-import type { FinishReason, GenerateOptions, LlmCallConfig, Message, TokenUsage } from '@deepseek-ai/dsh-llm'
+import { isDeepStrictEqual } from 'node:util'
+import type { ContentBlock, FinishReason, GenerateOptions, LlmCallConfig, Message } from '@deepseek-ai/dsh-llm'
 import { assertNever, BlockAssembler, HarnessError, deepFreeze } from '@deepseek-ai/dsh-llm'
 import { agentEvents, agentInterruptReasonOf, assembleContextFor } from '@deepseek-ai/dsh-agent'
 import type { AgentEventDispatch, ContinuationDecision, HookContext, PromptDecision } from '@deepseek-ai/dsh-agent'
@@ -95,23 +96,6 @@ function interruptionTurnEndReason(handle: LoopHandle, signal: AbortSignal): Tur
   }
 }
 
-/** Append the durable assembled assistant message when it carries content or usage. */
-function appendAssistantMessage(
-  session: Session,
-  turn: number,
-  step: number,
-  message: Message,
-  usage: TokenUsage | undefined,
-  chunkSeqs: number[],
-): void {
-  if (message.content.length === 0 && usage === undefined) return
-  session.append(
-    'assistant/message',
-    { turn, step, content: message.content, ...usage === undefined ? {} : { usage } },
-    { surfaceOp: 'append', ...(chunkSeqs.length > 0 ? { sourceEventSeqs: chunkSeqs } : {}) },
-  )
-}
-
 /** Mutable agent controls supplied to the loop driver. */
 export interface LoopHandle {
   /** Native-private agent inbox handed to the driver only at internal startup. */
@@ -288,10 +272,15 @@ async function runTurn(
       // `allow.content` REPLACES the prompt bytes (a rewrite); absent keeps them.
       const content = decision.content ?? message.content
       session.append('user/message', { content, source: message.source }, { surfaceOp: 'append' })
-      // `allow.additionalContext` is a SEPARATE context/message the next request
-      // also sees. The turn is open, so inject() appends it into THIS turn.
-      if (decision.additionalContext) {
-        agent.inject(decision.additionalContext.content, { source: decision.additionalContext.source })
+      // Every `allow.additionalContexts` entry is a separate context/message the
+      // next request also sees. The turn is open, so inject() appends each one
+      // into THIS turn without flattening provenance, framing, or metadata.
+      for (const context of decision.additionalContexts ?? []) {
+        agent.inject(context.content, {
+          source: context.source,
+          ...context.envelope !== undefined ? { envelope: context.envelope } : {},
+          ...context.meta !== undefined ? { meta: context.meta } : {},
+        })
       }
     }
 
@@ -485,13 +474,13 @@ async function runStep(
   const seedConfig: LlmCallConfig = deepFreeze(structuredClone(transmission.loggedHeader
     // eslint-disable-next-line @typescript-eslint/no-non-null-assertion -- loggedHeader ⟹ a snapshot is in the log
     ? session.requestHeader()!.config
-    : { model: options.model ?? '' }))
+    : { provider: options.provider ?? '', model: options.model ?? '' }))
 
   // Listener replacements are recorded in the request header before dispatch.
   const config = await events.waterfall('agent/request', turn, step, seedConfig, signal, () => Promise.resolve(seedConfig))
   interruptionCheckpoint(signal)
-  if (!config.model) {
-    throw new Error(`agent "${agent.id}" has no model: set AgentOptions.model or supply one via the agent/request waterfall`)
+  if (!config.provider || !config.model) {
+    throw new Error(`agent "${agent.id}" has no provider/model: set AgentOptions.provider and AgentOptions.model or supply both via the agent/request waterfall`)
   }
 
   // eslint-disable-next-line @typescript-eslint/no-non-null-assertion -- runTurn composes the prefix before every runStep call
@@ -508,6 +497,7 @@ async function runStep(
 
   // Freeze the logged header plus boundary snapshot; the prefix precedes derived history.
   const request: GenerateOptions = deepFreeze({
+    provider: header.config.provider,
     model: header.config.model,
     messages: [...header.messagePrefix ?? [], ...boundaryMessages],
     ...header.system !== undefined ? { system: header.system } : {},
@@ -535,20 +525,28 @@ async function runStep(
   if (stepError) throw stepError
 
   if (assembler.finish.kind === 'max-tokens') {
-    let message: Message = withoutToolCalls(assembler.message())
-    message = withoutToolCalls(await events.waterfall('agent/step-result', turn, step, message, signal, () => Promise.resolve(message)))
-    interruptionCheckpoint(signal)
+    const assembled = assembler.message()
+    const assembledContent = structuredClone(assembled.content)
+    let message: Message = withoutToolCalls(assembled)
+    message = withoutToolCalls(await processStepResult(
+      events, session, turn, step, header.config, assembledContent, message, assembler, chunkSeqs, signal,
+    ))
     // Preserve usage even when max-token truncation produced no content.
-    appendAssistantMessage(session, turn, step, message, assembler.usage, chunkSeqs)
+    recordAssistantMessage(session, turn, step, header.config, assembledContent, message, assembler, chunkSeqs)
     return { hadToolCalls: false, finish: assembler.finish }
   }
 
   // Record the post-waterfall message that tool dispatch uses.
-  let message: Message = assembler.message()
-  message = await events.waterfall('agent/step-result', turn, step, message, signal, () => Promise.resolve(message))
-  interruptionCheckpoint(signal)
+  const assembled = assembler.message()
+  const assembledContent = structuredClone(assembled.content)
+  let message: Message = assembled
+  message = await processStepResult(
+    events, session, turn, step, header.config, assembledContent, message, assembler, chunkSeqs, signal,
+  )
 
-  appendAssistantMessage(session, turn, step, message, assembler.usage, chunkSeqs)
+  // Every successful call records its completion anchor, including explicit
+  // empty chunk provenance for a contentless, usage-less provider response.
+  recordAssistantMessage(session, turn, step, header.config, assembledContent, message, assembler, chunkSeqs)
 
   // Tool execution stays sequential; recheck abort around each normalized result.
   const toolCalls = message.content.filter(block => block.type === 'tool-call')
@@ -583,18 +581,95 @@ async function runStep(
       // Persist tool-owned presentation data for replay.
       ...result.meta !== undefined ? { meta: result.meta } : {},
     }, { surfaceOp: 'append', sourceEventSeqs: [callEvent.seq] })
-    if (result.additionalContext) pendingContext.push(result.additionalContext)
+    pendingContext.push(...result.additionalContexts ?? [])
     interruptionCheckpoint(signal)
   }
 
   // Append buffered context after the complete result batch.
   for (const context of pendingContext) {
-    agent.inject(context.content, { source: context.source })
+    agent.inject(context.content, {
+      source: context.source,
+      ...context.envelope !== undefined ? { envelope: context.envelope } : {},
+      ...context.meta !== undefined ? { meta: context.meta } : {},
+    })
   }
 
   return { hadToolCalls: toolCalls.length > 0, finish: assembler.finish }
 }
 
+/** Preserve successful-call accounting without retaining output that result processing rejected. */
+async function processStepResult(
+  events: AgentEventDispatch,
+  session: Session,
+  turn: number,
+  step: number,
+  config: LlmCallConfig,
+  assembledContent: ContentBlock[],
+  message: Message,
+  assembler: BlockAssembler,
+  chunkSeqs: number[],
+  signal: AbortSignal,
+): Promise<Message> {
+  try {
+    const processed = await events.waterfall(
+      'agent/step-result', turn, step, message, signal, () => Promise.resolve(message),
+    )
+    interruptionCheckpoint(signal)
+    return processed
+  } catch (error: unknown) {
+    recordAssistantMessage(
+      session,
+      turn,
+      step,
+      config,
+      assembledContent,
+      { ...message, content: [] },
+      assembler,
+      chunkSeqs,
+      false,
+    )
+    throw error
+  }
+}
+
+/** Record one content-or-usage assistant message with replay-safe provenance. */
+function recordAssistantMessage(
+  session: Session,
+  turn: number,
+  step: number,
+  config: LlmCallConfig,
+  assembledContent: ContentBlock[],
+  message: Message,
+  assembler: BlockAssembler,
+  chunkSeqs: number[],
+  preserveReplayState = true,
+): void {
+  session.append(
+    'assistant/message',
+    {
+      turn,
+      step,
+      content: message.content,
+      provenance: assistantProvenance(
+        config,
+        assembler.replayState,
+        preserveReplayState && isDeepStrictEqual(message.content, assembledContent),
+      ),
+      ...assembler.usage === undefined ? {} : { usage: assembler.usage },
+    },
+    { surfaceOp: 'append', sourceEventSeqs: chunkSeqs },
+  )
+}
+
+/** Build durable assistant provenance, dropping replay state after any content rewrite. */
+function assistantProvenance(config: LlmCallConfig, replayState: unknown, contentUnchanged: boolean): NonNullable<Message['provenance']> {
+  return {
+    provider: config.provider,
+    model: config.model,
+    ...contentUnchanged && replayState !== undefined ? { replayState } : {},
+  }
+}
+
 function withoutToolCalls(message: Message): Message {
   return { ...message, content: message.content.filter(block => block.type !== 'tool-call') }
 }

packages/core/agent-loop/src/request-log.ts

@@ -1,11 +1,12 @@
 /**
  * Per-loop-instance request-header bookkeeping for reconstructability. The
- * comparison baseline is the header folded from the session log, so a fresh
- * loop instance needs no special resume or fork state.
+ * comparison baseline is folded from the session log; a fresh instance anchors
+ * it with an initial/resume snapshot and later logs full changed snapshots.
+ *
  * @module dsh-agent-loop/request-log
  */
 
-import { diffHeader, headerEquals, applyHeaderDelta } from '@deepseek-ai/dsh-session'
+import { headerEquals } from '@deepseek-ai/dsh-session'
 import type { EpochHeader, Session } from '@deepseek-ai/dsh-session'
 import type { Message } from '@deepseek-ai/dsh-llm'
 
@@ -32,10 +33,8 @@ export function createTransmissionLog(): TransmissionLog {
 }
 
 /**
- * Append whatever header event makes the log reproduce this request's header.
- * The first request from an instance always records a full `initial` or `resume`
- * snapshot. Later requests record nothing when unchanged, a round-tripping
- * delta when expressible, or a full `fallback` snapshot otherwise.
+ * Append the full header snapshot owed by this request: initial/resume for the
+ * instance's first request, nothing when unchanged, or change otherwise.
  *
  * @param session - the session whose log explains the request.
  * @param state - this loop instance's bookkeeping (mutated on first log).
@@ -52,12 +51,5 @@ export function recordRequestHeader(session: Session, state: TransmissionLog, he
   // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
   const baseline = session.requestHeader()!
   if (headerEquals(baseline, header)) return
-  const delta = diffHeader(baseline, header)
-  /* v8 ignore next -- headerEquals false ⟹ diffHeader defined: both compare the same four parts */
-  if (delta === undefined) return
-  if (headerEquals(applyHeaderDelta(baseline, delta), header)) {
-    session.append('request/header-delta', delta)
-  } else {
-    session.append('request/header', { header, reason: 'fallback' })
-  }
+  session.append('request/header', { header, reason: 'change' })
 }