feat(agent): improve investigation contracts and runtime readiness

src/routes/chatStream.ts

@@ -332,7 +332,7 @@ export const streamPromptResponse = async ({
         emittedText = true;
         done = true;
       }
-    } else await runtime.prompt(sessionId, message, toRuntimeModel(model));
+    } else await runtime.prompt(sessionId, message, toRuntimeModel(model), undefined, signal);
     onPromptDispatched?.();
   })
     .then(() => {
@@ -1048,7 +1048,7 @@ export const streamPromptResponse = async ({
           // the same managed session/lease, never create another task run.
           finalAnswer = undefined;
           sawResponseActivity = false;
-          await runtime.prompt(sessionId, typeof idleDecision === "string" ? idleDecision : "请处理收信箱中新到达的调查协作消息，按需回复，然后完成本轮工作。", toRuntimeModel(model));
+          await runtime.prompt(sessionId, typeof idleDecision === "string" ? idleDecision : "请处理收信箱中新到达的调查协作消息，按需回复，然后完成本轮工作。", toRuntimeModel(model), undefined, signal);
           continue;
         }
         if (waitForUserInput && await waitForUserInput()) {

src/routes/chatStreamRoute.ts

@@ -29,7 +29,7 @@ import { type FrontendActionCoordinator } from "../frontendAction/coordinator.js
 import { type LearningOrchestrator } from "../learning/orchestrator.js";
 import { logger } from "../logger.js";
 import { type MemoryStore } from "../memory/store.js";
-import { type OpencodeRuntimeAdapter } from "../runtime/opencode.js";
+import { McpPreparationError, type OpencodeRuntimeAdapter } from "../runtime/opencode.js";
 import {
   getRuntimeSessionContext,
   setRuntimeSessionContext,
@@ -498,6 +498,11 @@ export const registerChatStreamRoute = (
       const taskContext = sessionPurpose === "task_collaboration"
         ? resolvedTaskContext
         : null;
+      const taskSource = z.object({ replay_context: z.record(z.unknown()).nullish() }).passthrough()
+        .safeParse(resolvedTaskContext?.task.source);
+      setRuntimeSessionContext({ ...getRuntimeSessionContext(binding.sessionId)!,
+        taskWorkflow: resolvedTaskContext?.task.workflow,
+        taskReplay: taskSource.success && !!taskSource.data.replay_context });
       if (taskContext) {
         const report = taskContext.selected_report ?? taskContext.task.latest_report;
         const reference = z.object({ revision: z.number().int().positive() }).passthrough().safeParse(report);
@@ -1178,7 +1183,10 @@ export const registerChatStreamRoute = (
           }
         }
       } catch (error) {
-        publish("error", { session_id: clientSessionId, message: abortController.signal.aborted ? "请求已中断" : "Agent response failed" });
+        const preparationFailure = error instanceof McpPreparationError ? error : null;
+        publish("error", { session_id: clientSessionId,
+          message: abortController.signal.aborted ? "请求已中断" : preparationFailure?.message ?? "Agent response failed",
+          ...(preparationFailure && !abortController.signal.aborted ? { code: preparationFailure.code } : {}) });
         await stopTaskHeartbeat();
         if (
           sessionPurpose === "task_execution" &&
@@ -1192,7 +1200,7 @@ export const registerChatStreamRoute = (
               activeSessionRecord.taskId,
               activeSessionRecord.runId,
               clientSessionId,
-              abortController.signal.aborted ? "AGENT_ABORTED" : "AGENT_EXECUTION_ERROR",
+              abortController.signal.aborted ? "AGENT_ABORTED" : preparationFailure?.code ?? "AGENT_EXECUTION_ERROR",
               abortController.signal.aborted
                 ? "Agent execution was aborted"
                 : error instanceof Error ? error.message : "Agent execution failed",