refactor(agent): simplify inbox-driven turn admission

packages/client/runtime/tests/event-script.ts

@@ -82,7 +82,12 @@ export const ev = {
       },
     }),
   turnEnd: (seq: number, turn: number, reason: 'completed' | 'aborted' | 'disposed' = 'completed'): SessionEvent =>
-    at(seq, { type: 'turn/end', data: { turn, reason: { kind: reason } } }),
+    at(seq, { type: 'turn/end', data: {
+      turn,
+      reason: reason === 'completed'
+        ? { kind: 'completed' }
+        : { kind: 'aborted', reason: { kind: reason === 'disposed' ? 'disposed' : 'user' } },
+    } }),
   commandRun: (seq: number, commandId: string, name: string, args = ''): SessionEvent =>
     at(seq, { type: 'command/run', data: { commandId, name, args, source: { kind: 'user' } } }),
   commandDone: (seq: number, commandId: string, kind: 'success' | 'error' = 'success', text?: string): SessionEvent =>

packages/client/runtime/tests/request-inspection.spec.ts

@@ -225,20 +225,15 @@ describe('inspectRequests', () => {
     const snapshot = inspectRequests(entriesOf([
       at(0, 'step/start', { turn: 1, step: 1 }),
       at(1, 'turn/end', {
-        turn: 1,
-        reason: {
-          kind: 'error',
-          step: 1,
-          failure: {
-            code: 'AUTH',
-            message: 'Authentication Fails, Your api key: sk-preview-secret is invalid',
-          },
+        turn: 1, step: 1, reason: { kind: 'error', error: {
+          code: 'AUTH',
+          message: 'Authentication Fails, Your api key: sk-preview-secret is invalid',
+        },
         },
       }),
       at(2, 'step/start', { turn: 2, step: 1 }),
       at(3, 'turn/end', {
-        turn: 2,
-        reason: { kind: 'error', step: 1, message: 'plugin exploded' },
+        turn: 2, step: 1, reason: { kind: 'error', error: 'plugin exploded' },
       }),
     ]))
 

packages/client/runtime/tests/session.spec.ts

@@ -162,7 +162,7 @@ describe('live event path', () => {
     expect((last as { interrupted?: true }).interrupted).toBeUndefined()
   })
 
-  it('retracts the failed step partial on retry and keeps a replayable notice before the recovered response', async () => {
+  it('retracts the failed-attempt partial and starts the retry on new chunk evidence', async () => {
     const { session } = await opened()
     const feed = (event: SessionEvent) => { session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event }) }
     const retryTurn = [
@@ -171,25 +171,13 @@ describe('live event path', () => {
       ev.stepStart(8, 1),
       ev.chunkStart(9, 1),
       ev.chunkText(10, 1, '不完整回复'),
-      ev.stepEnd(11, 1),
-      ev.retry(12, 1, 0, 1, 2, 450, '连接被重置'),
-      at(13, {
-        type: 'turn/end',
-        data: {
-          turn: 1,
-          reason: {
-            kind: 'error', step: 0,
-            failure: { code: 'TRANSPORT', message: '连接被重置' },
-          },
-        },
-      }),
-      at(14, { type: 'turn/start', data: { turn: 2, trigger: { kind: 'retry' } } }),
-      ev.stepStart(15, 2),
-      ev.assistant(16, 2, '完整回复'),
-      ev.stepEnd(17, 2),
-      ev.turnEnd(18, 2),
+      ev.retry(11, 1, 0, 1, 2, 450, '连接被重置'),
+      ev.chunkStart(12, 1),
+      ev.assistant(13, 1, '完整回复'),
+      ev.stepEnd(14, 1),
+      ev.turnEnd(15, 1),
     ]
-    for (const event of retryTurn.slice(0, 7)) feed(event)
+    for (const event of retryTurn.slice(0, 6)) feed(event)
 
     let snapshot = session.getSnapshot()
     expect(snapshot.partial).toBeNull()
@@ -208,7 +196,7 @@ describe('live event path', () => {
     })
     expect(JSON.stringify(snapshot.nodes)).not.toContain('不完整回复')
 
-    for (const event of retryTurn.slice(7)) feed(event)
+    for (const event of retryTurn.slice(6)) feed(event)
     snapshot = session.getSnapshot()
     expect(snapshot.nodes.slice(-2).map(node => node.kind)).toEqual(['model-retry', 'assistant'])
     expect(snapshot.nodes.some(node => node.kind === 'turn-error')).toBe(false)
@@ -230,33 +218,30 @@ describe('live event path', () => {
     const failedTurns = [
       ev.turnStart(6, 1),
       ev.user(7, '鉴权失败'),
-      at(8, {
+      ev.stepStart(8, 1),
+      at(9, {
         type: 'turn/end',
-        data: {
-          turn: 1,
-          reason: {
-            kind: 'error',
-            step: 0,
-            failure: {
-              code: 'AUTH',
-              message: 'Authentication Fails, Your api key: sk-preview-secret is invalid',
-            },
-          },
+        data: { turn: 1, step: 0, reason: { kind: 'error', error: {
+          code: 'AUTH',
+          message: 'Authentication Fails, Your api key: sk-preview-secret is invalid',
+        },
+        },
         },
       }),
-      ev.turnStart(9, 2),
-      ev.user(10, '内部失败'),
-      at(11, {
+      ev.turnStart(10, 2),
+      ev.user(11, '内部失败'),
+      ev.stepStart(12, 2, 1),
+      at(13, {
         type: 'turn/end',
-        data: { turn: 2, reason: { kind: 'error', step: 1, message: 'plugin exploded' } },
+        data: { turn: 2, step: 1, reason: { kind: 'error', error: 'plugin exploded' } },
       }),
     ]
     for (const event of failedTurns) feed(event)
 
     const errors = session.getSnapshot().nodes.filter(node => node.kind === 'turn-error')
     expect(errors).toMatchObject([
-      { seq: 8, turn: 1, step: 0, code: 'AUTH', message: 'API key is invalid' },
-      { seq: 11, turn: 2, step: 1, message: 'plugin exploded' },
+      { seq: 9, turn: 1, step: 0, code: 'AUTH', message: 'API key is invalid' },
+      { seq: 13, turn: 2, step: 1, message: 'plugin exploded' },
     ])
     expect('code' in errors[1]!).toBe(false)
 
@@ -395,7 +380,7 @@ describe('live event path', () => {
   })
 
   it.each(['aborted', 'disposed'] as const)(
-    'marks a scheduled retry as cancelled when its failed turn ends %s',
+    'marks a scheduled retry as cancelled when its failed turn receives the %s cause',
     async (reason) => {
       const { session } = await opened()
       const feed = (event: SessionEvent) => {
@@ -415,6 +400,24 @@ describe('live event path', () => {
     },
   )
 
+  it('marks a scheduled retry as started when its failed turn ends with an error', async () => {
+    const { session } = await opened()
+    const feed = (event: SessionEvent) => {
+      session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event })
+    }
+    feed(ev.turnStart(6, 1))
+    feed(ev.retry(7, 1))
+    feed(at(8, {
+      type: 'turn/end',
+      data: { turn: 1, step: 0, reason: { kind: 'error', error: 'retry failed' } },
+    }))
+
+    expect(session.getSnapshot().nodes.at(-1)).toMatchObject({
+      kind: 'model-retry',
+      retryState: 'started',
+    })
+  })
+
   it('freezes an unfinalized partial into an interrupted node on turn/end (cancel path)', async () => {
     const { session } = await opened()
     const feed = (event: SessionEvent) => { session.handleMuxEnvelope('r' as never, { type: 'session/event', sessionId: SID, event }) }