🐛 Bug: NodeFetchHandler hung

♻️ Reproduction Steps

import { createControllerModule } from "@ai/apis/common/controller-module.factory";
import { V1Controller } from "@ai/apis/common/decorators";
import { jsonStringify } from "@ai/common/utils/json";
import { CopilotKitService } from "@ai/domains/copilot-kit/copilot-kit.interface";
import { CopilotKitModule } from "@ai/domains/copilot-kit/copilot-kit.module";
import {
  BuiltInAgent,
  CopilotKitIntelligence,
  CopilotRuntime,
  createCopilotRuntimeHandler,
} from "@copilotkit/runtime/v2";
import { createCopilotNodeHandler } from "@copilotkit/runtime/v2/node";
import { All, Inject, Logger, Req, Res } from "@nestjs/common";
import { ApiExcludeController } from "@nestjs/swagger";
import type { Request, Response } from "express";

@ApiExcludeController(true)
@V1Controller("/copilotkit")
export class CopilotKitController {
  private readonly logger = new Logger(CopilotKitController.name);


  @All()
  async copilotkit(

    @Req() req: Request,
    @Res() res: Response,
  ) {
    const builtInAgent = new BuiltInAgent({
      model: "openai:gpt-5.4-mini",
    });
    const runtime = new CopilotRuntime({
      agents: { default: builtInAgent }, //,
      intelligence: new CopilotKitIntelligence({
        apiKey: "fake",
      }),
      // Threads are per-user. Without this, every visitor shares one history.
      identifyUser: (request) => ({
        id: request.headers.get("x-user-id") ?? "anonymous",
        name: request.headers.get("x-user-name") ?? "Anonymous",
      }),
    });
    const handler = createCopilotNodeHandler(
      createCopilotRuntimeHandler({
        runtime,
        basePath: "/api/v1/copilotkit",
      }),
    );

    return handler(req, res);
  }
}

export const CopilotKitApiControllerModule = createControllerModule(
  CopilotKitController,
  [CopilotKitModule],
);

curl --url 'http://127.0.0.1:3333/api/v1/copilotkit' \
  -H 'Accept: */*' \
  -H 'Accept-Language: en-US,en;q=0.5' \
  -H 'Cache-Control: no-cache' \
  -H 'Connection: keep-alive' \
  -H 'Content-Type: application/json' \
  -H 'DNT: 1' \
  -H 'Origin: http://localhost:3000' \
  -H 'Pragma: no-cache' \
  -H 'Referer: http://localhost:3000/' \
  -H 'Sec-Fetch-Dest: empty' \
  -H 'Sec-Fetch-Mode: cors' \
  -H 'Sec-Fetch-Site: cross-site' \
  -H 'Sec-GPC: 1' \
  -H 'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/152.0.0.0 Safari/537.36' \
  -H 'sec-ch-ua: "Chromium";v="152", "Not?A_Brand";v="24", "Brave";v="152"' \
  -H 'sec-ch-ua-mobile: ?0' \
  -H 'sec-ch-ua-platform: "macOS"' \
  --data-raw '{"method":"info"}'

✅ Expected Behavior

return normally

❌ Actual Behavior

/api/v1/copilotkit hung

Screenshots

No response

𝌚 CopilotKit Version

server side

npm ls | grep "@copilotkit"
├── @copilotkit/runtime@1.70.0 -> ./node_modules/.pnpm/@copilotkit+runtime@1.70.0_@cfworker+json-schema@4.1.1_@langchain+core@1.2.9_@opentelem_de5cf5235a9d6d68a70fb5c89ec0b6c1/node_modules/@copilotkit/runtime
├── @copilotkit/shared@1.70.0 -> ./node_modules/.pnpm/@copilotkit+shared@1.70.0_@ag-ui+core@0.0.59/node_modules/@copilotkit/shared


web site

 npm ls | grep "@copilotkit"
├── @copilotkit/react-core@1.56.4
├── @copilotkit/react-ui@1.56.4
├── @copilotkit/runtime@1.56.4

📄 Logs (Optional)

server side log

2026-09-02 11:21:20.964 - 01a06022-af40-7aa2-8fda-3859e0c1ff19 -  DEBUG [LoggingInterceptor] POST=>/api/v1/copilotkit | query: {} | params: {} | body: {"method":"info"}

Start with the NodeFetchHandler path used by createCopilotNodeHandler and createCopilotRuntimeHandler in the provided NestJS controller. Reproduce the hang with the supplied curl request and compare the handler's behavior for the {"method":"info"} payload. Done means the /api/v1/copilotkit request returns normally instead of remaining open.