Function start

tools/debug-console/app/api/chat/route.ts:138–187

(controller)

  const stream = new ReadableStream({
    async start(controller) {
      let closed = false;
      const safeEnqueue = (chunk: Uint8Array) => {
        if (closed) return;
        try {
          controller.enqueue(chunk);
        } catch {
          // controller 已关闭——忽略
          closed = true;
        }
      };
      // 整段逻辑跑在 workspaceContext 作用域内：root_index 预热 + runAgent 深处的所有
      // executeTool 都会读到 workspace，并在调 web 时带上 kb_workspace cookie。
      await workspaceContext.run(workspace, async () => {
        try {
          const baseSystem = system || DEFAULT_SYSTEM_PROMPT;
          const indexContent = await getRootIndexContent(workspace);
          const augmentedSystem = appendPrewarmedIndex(baseSystem, indexContent);

          for await (const evt of runAgent({
            provider,
            model,
            system: augmentedSystem,
            messages,
            toolBudget: tool_budget,
            mode,
            signal: abortController.signal,
          })) {
            if (abortController.signal.aborted) break;
            safeEnqueue(sseLine(evt));
          }
          safeEnqueue(sseLine({ kind: "stream-end" }));
        } catch (e) {
          safeEnqueue(
            sseLine({
              kind: "turn-end",
              reason: "error",
              error_message: e instanceof Error ? e.message : String(e),
            }),
          );
        } finally {
          closed = true;
          try {
            controller.close();
          } catch {
            /* 已关闭 */
          }
        }
      });
    },
    cancel() {
      // 客户端拉断 stream（fetch abort）→ 转发到 agent-loop
      abortController.abort();