refactor: identify and freeze messages at creation

packages/subagent/subagent-inprocess/src/index.ts

@@ -11,7 +11,7 @@ import { randomUUID } from 'node:crypto'
 import type { Context } from 'cordis'
 import type { Agent, AgentOptions } from '@deepseek-ai/dsh-agent'
 import { findLastMessageTurnEnd, SessionId, type SessionEvent, type TurnEndReason } from '@deepseek-ai/dsh-session'
-import type { ContentBlock } from '@deepseek-ai/dsh-llm'
+import { createUserMessage, type ContentBlock } from '@deepseek-ai/dsh-llm'
 import { assertSubagentMaxDepth, delegationDepthOf } from '@deepseek-ai/dsh-subagent'
 import type { SubagentResult, SubagentRun, SubagentStartRequest, SubagentStopReason } from '@deepseek-ai/dsh-subagent'
 import {
@@ -141,7 +141,7 @@ export async function startInProcessRun(
 
   const result: Promise<SubagentResult> = (async () => {
     try {
-      child.followup({ content: request.prompt, source: { kind: 'user' } })
+      child.followup(createUserMessage({ content: request.prompt, source: { kind: 'user' } }))
       await child.whenIdle()
       return readResult(
         child,
@@ -176,7 +176,7 @@ function readResult(
   const own = child.session.events.slice(seedLength)
   const lastMessage = own.findLast((event): event is SessionEvent<'assistant/message'> => event.type === 'assistant/message')
   const lastEnd = findLastMessageTurnEnd(own)
-  const output: ContentBlock[] = lastMessage?.data.content ?? []
+  const output: ContentBlock[] = lastMessage?.data.message.content ?? []
   const recorded = toStopReason(lastEnd?.data.reason)
   // Disposal can tear the owner down before the loop records its ordinary
   // `aborted` end, yielding `disposed` instead. A requested cancellation owns