Merge remote-tracking branch 'origin/master' into codex/send-one-turn

# Conflicts:
#	docs/architecture.md
#	docs/core-data-structures/core.md
#	docs/rfc/implemented/feature/2026-06-30-interception-seams.md
#	packages/core/agent-loop/src/loop.ts
#	packages/core/agent/src/types.ts

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

@@ -8,7 +8,7 @@
 
 import type { Context } from 'cordis'
 import { agentEvents } from '@deepseek-ai/dsh-agent'
-import type { AgentId, AgentOptions, AgentStatus, SendOptions } from '@deepseek-ai/dsh-agent'
+import type { 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'
@@ -225,14 +225,20 @@ 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
@@ -244,7 +250,7 @@ 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/loop.ts

@@ -217,10 +217,15 @@ async function runTurn(
       // `allow.content` REPLACES the prompt bytes (a rewrite); absent keeps them.
       const content = promptDecision.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 (promptDecision.additionalContext) {
-        agent.inject(promptDecision.additionalContext.content, { source: promptDecision.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 promptDecision.additionalContexts ?? []) {
+        agent.inject(context.content, {
+          source: context.source,
+          ...context.envelope !== undefined ? { envelope: context.envelope } : {},
+          ...context.meta !== undefined ? { meta: context.meta } : {},
+        })
       }
     }
 
@@ -567,7 +572,7 @@ 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 ?? [])
     // The signal may flip while the tool is awaited.
     /* v8 ignore start -- signal.reason default unreachable: cancel()/disposal always set it */
     // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
@@ -577,7 +582,11 @@ async function runStep(
 
   // 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 }