fix(subagent): keep the closing message when another tool ran beside the relay

- subagent: a send_message that shares its step with another tool call no longer omits the closing message
- tests: read settled job results through job_output and give job-owning test agents a mutable inbox

packages/experimental/tool-terminal/tests/tools.spec.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from 'vitest'
-import { provideWorkingDirectoryFixture, unsupportedInbox } from '@deepseek-ai/dsh-agent-loop-testkit'
+import { createInboxStub, provideWorkingDirectoryFixture } from '@deepseek-ai/dsh-agent-loop-testkit'
 import { Context } from '@deepseek-ai/cordis'
 import { ToolCallId } from '@deepseek-ai/dsh-llm'
 import { Session, SessionId } from '@deepseek-ai/dsh-session'
@@ -20,7 +20,7 @@ async function fakeAgent(ctx: Context, rawId: string): Promise<Agent> {
   const id = SessionId(rawId)
   const session = Session.create(id)
   const agent: Agent = {
-    id, options: {}, session, inbox: unsupportedInbox(),
+    id, options: {}, session, inbox: createInboxStub(),
     status: 'idle',
     ctx: scope.ctx,
     send: () => {},

packages/jobs/tool-jobs/tests/tool-jobs.spec.ts

@@ -82,10 +82,10 @@ async function fakeAgent(ctx: Context, sessionId: string, delivery: FakeDelivery
     ctx: scopeFiber.ctx,
     inject: delivery.inject ?? (() => {}),
     followup: delivery.followup ?? (() => {}),
-    inbox: { remove: delivery.remove ?? (() => true) },
     status: delivery.status ?? 'running',
     session: { id, header: { version: 0, id, createdAt: 0 } },
   } as unknown as Agent
+  Object.assign(agent, { inbox: { remove: delivery.remove ?? (() => true) } })
   agentRegistryDisposers.set(agent, await ctx.agents.register(agent))
   agentScopeFibers.set(agent, scopeFiber)
   return agent

packages/subagent/subagent/src/activation.ts

@@ -73,11 +73,14 @@ interface ActivationBase {
   announced: boolean
   /**
    * Whether this child's last action before its closing text was a message to
-   * its direct parent: no input was claimed and no tool call started since.
+   * its direct parent: the only tool call of its step, with no input claimed
+   * and no tool call started since.
    * Its settlement notice then omits the closing message, which restates that
    * message.
    */
   relayed: boolean
+  /** Tool calls started in the child's current step, which decides {@link relayed}. */
+  stepToolCalls: number
 }
 
 /** Resources retained only for the selected execution kind. */

packages/subagent/subagent/src/manager.ts

@@ -935,6 +935,7 @@ export class SubagentManager {
       observer,
       announced: false,
       relayed: false,
+      stepToolCalls: 0,
     }
     void activation.result.promise.catch(() => undefined)
     this.resident.set(childId, activation)
@@ -949,10 +950,16 @@ export class SubagentManager {
         activation.handle.agent.ctx.on('agent/inbox/inserted', wakeSettlement)
         activation.handle.agent.ctx.on('agent/inbox/claimed', wakeSettlement)
         activation.handle.agent.ctx.on('agent/inbox/discarded', wakeSettlement)
-        // Input or a tool call after the child's last message to its parent
-        // means the closing text may report work that message did not.
+        // Input, a later tool call, or another call in the same step as the
+        // child's message to its parent means the closing text may report work
+        // that message did not.
         activation.handle.agent.ctx.on('agent/inbox/claimed', () => { activation.relayed = false })
+        activation.handle.agent.ctx.on('agent/pre-step', (_payload, next) => {
+          activation.stepToolCalls = 0
+          return next()
+        })
         activation.handle.agent.ctx.on('tools/pre-execute', (_exec, next) => {
+          activation.stepToolCalls += 1
           activation.relayed = false
           return next()
         })
@@ -1307,7 +1314,7 @@ export class SubagentManager {
     }
     const message = createAgentMessage(sender, content)
     this.sendAgentMessage(parent, message)
-    activation.relayed = true
+    activation.relayed = activation.stepToolCalls <= 1
     return message.id
   }
 

packages/subagent/subagent/tests/continuation.spec.ts

@@ -3060,6 +3060,49 @@ describe('continuable settlement delivery', () => {
     )
   })
 
+  it('reports the closing message when another tool ran in the same step as the message', async () => {
+    let childTurns = 0
+    const respond = (options: GenerateOptions): StreamChunk[] => {
+      const history = JSON.stringify(options.messages)
+      if (!history.includes('Your parent agent id is')) return textResponse('parent ack')
+      childTurns += 1
+      if (childTurns > 1) return textResponse('the answer')
+      const parentId = /Your parent agent id is \\"([^\\]+)\\"/.exec(history)![1]!
+      const calls = [
+        { id: ToolCallId('n1'), name: 'noop', arguments: '{}' },
+        { id: ToolCallId('s1'), name: 'send_message', arguments: JSON.stringify({ agent_id: parentId, message: 'interim' }) },
+      ]
+      return [
+        ...calls.flatMap((call, index): StreamChunk[] => [
+          { type: 'block-start', index, blockType: 'tool-call' },
+          { type: 'tool-call-delta', index, id: call.id, name: call.name, argumentsDelta: call.arguments },
+          { type: 'block-end', index, block: { type: 'tool-call', ...call } },
+        ]),
+        { type: 'usage', usage: { inputTokens: 10, outputTokens: 5 } },
+        { type: 'finish', reason: { kind: 'tool-calls' } },
+      ]
+    }
+    const { ctx, parent } = await setup(Array.from({ length: 6 }, () => respond))
+    await ctx.plugin(SubagentControl)
+    ctx.tools.register(defineTool({
+      name: 'noop',
+      description: 'does nothing',
+      parameters: {},
+      output: {
+        schema: { type: 'object', additionalProperties: false, properties: {} },
+        render: () => [{ type: 'text', text: 'noop' }],
+      },
+      execute: () => Promise.resolve({}),
+    }))
+    const started = await ctx.subagents.startActivation({ ...startSpec(parent), delivery: 'parent' })
+    await waitNoActivation(ctx, started.childId)
+
+    await vi.waitFor(() => { expect(settlementNotices(parent)).toHaveLength(1) })
+    expect(settlementNotices(parent)[0]!.text).toBe(
+      `Background subagent ${started.childId} finished and will do no further work unless you send it more.\nIts closing message:\nthe answer`,
+    )
+  })
+
   it('delivers the terminal reason when the child never had a chance to report', async () => {
     const { ctx, parent } = await setup([maxTokensResponse('half an ans'), textResponse('parent ack')])
     const started = await ctx.subagents.startActivation({ ...startSpec(parent), delivery: 'parent' })

packages/workflow/tool-workflow/tests/tool-workflow.spec.ts

@@ -6,7 +6,7 @@ import SystemPrompt from '@deepseek-ai/dsh-system-prompt'
 import ToolRuntime, { TOOL_ABORTED_BEFORE_DISPATCH } from '@deepseek-ai/dsh-tools'
 import type { ToolExecutionResult, ToolExecutionToken } from '@deepseek-ai/dsh-tools'
 import type { Agent } from '@deepseek-ai/dsh-agent'
-import { unsupportedInbox } from '@deepseek-ai/dsh-agent-loop-testkit'
+import { createInboxStub } from '@deepseek-ai/dsh-agent-loop-testkit'
 import { WorkflowRunId, WorkflowEngine } from '@deepseek-ai/dsh-workflow'
 import type {
   WorkflowAgentEndInfo, WorkflowAgentInfo, WorkflowResult, WorkflowRun,
@@ -457,7 +457,7 @@ describe('dsh-tool-workflow', () => {
       const engine = ctx.workflowEngine as StubEngine
       const session = Session.create(SessionId('caller'))
       const parent: Agent = {
-        id: session.id, options: {}, session, inbox: unsupportedInbox(), status: 'idle', ctx,
+        id: session.id, options: {}, session, inbox: createInboxStub(), status: 'idle', ctx,
         send: () => {}, followup: () => {}, steer: () => {}, inject: () => {}, cancel: () => {},
         runMaintenance: task => task(new AbortController().signal), whenIdle: () => Promise.resolve(),
       }
@@ -511,9 +511,16 @@ describe('dsh-tool-workflow', () => {
       const settled = jobs.get(job.id, parent.id)
       expect(settled.detail).toBe('4 agents')
       expect(settled.progress).toBeUndefined()
-      const read = jobs.read(job.id, parent.id)
-      expect(read.result).toContain('workflow "audit" completed (4 agents)')
-      expect(read.result).toContain('"findings": 2')
+      const read = await ctx.tools.execute({
+        signal: testToolSignal,
+        callId: ToolCallId('call-settled-read'),
+        name: 'job_output',
+        arguments: { job_id: jobId },
+        agent: parent,
+      })
+      const readText = (read.content[0] as { text: string }).text
+      expect(readText).toContain('workflow "audit" completed (4 agents)')
+      expect(readText).toContain('"findings": 2')
       expect(engine.disposed).toBe(1)
       // The durable session record still brackets the background run.
       expect(session.snapshotEvents().map(event => event.type)).toEqual([
@@ -676,7 +683,7 @@ describe('dsh-tool-workflow', () => {
       await ctx.plugin(toolWorkflow, {})
       const session = Session.create(SessionId('caller'))
       const parent: Agent = {
-        id: session.id, options: {}, session, inbox: unsupportedInbox(), status: 'idle', ctx,
+        id: session.id, options: {}, session, inbox: createInboxStub(), status: 'idle', ctx,
         send: () => {}, followup: () => {}, steer: () => {}, inject: () => {}, cancel: () => {},
         runMaintenance: task => task(new AbortController().signal), whenIdle: () => Promise.resolve(),
       }
@@ -696,7 +703,14 @@ describe('dsh-tool-workflow', () => {
       expect(jobs.get(jobId, parent.id).detail).toBe('0 agents')
       const ring = jobs.readAt(jobId, 0, parent.id).chunks.map(chunk => chunk.text).join('')
       expect(ring).toContain('halfway')
-      expect(jobs.read(jobId, parent.id).result).toContain('"ok": true')
+      const read = await ctx.tools.execute({
+        signal: testToolSignal,
+        callId: ToolCallId('call-ptc-settled-read'),
+        name: 'job_output',
+        arguments: { job_id: jobId },
+        agent: parent,
+      })
+      expect((read.content[0] as { text: string }).text).toContain('"ok": true')
     }, 15_000)
   })
 })