OpenAI /responses endpoint silently hangs 10-28% of concurrent requests with no error

What this error means

/v1/responses endpoint silently drops 10-28% of concurrent requests under moderate load (5 simultaneous calls); TCP connection hangs indefinitely with no HTTP error or timeout is a OpenAI API failure pattern reported for developers trying to fix openai api responses endpoint hanging silently on concurrent requests without returning errors or timeouts. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

Reported on openai-python#3054 (2026-04-03). Affects GPT-5.1/GPT-5.4 /responses endpoint under moderate concurrent load. 10-28% of requests receive no HTTP error, no timeout, no retry — TCP connection simply hangs. Critical production impact for paid API users. Category: OpenAI API (direct API endpoint error).

Common causes

• Reported on openai-python#3054 (2026-04-03). Affects GPT-5.1/GPT-5.4 /responses endpoint under moderate concurrent load. 10-28% of requests receive no HTTP error, no timeout, no retry — TCP connection simply hangs. Critical production impact for paid API users. Category: OpenAI API (direct API endpoint error).

Quick fixes

1. Confirm the exact error signature matches /v1/responses endpoint silently drops 10-28% of concurrent requests under moderate load (5 simultaneous calls); TCP connection hangs indefinitely with no HTTP error or timeout.
2. Check the OpenAI API account, local tool state, and provider configuration involved in the failing workflow.
3. Reduce request pressure, check quota or plan limits, and retry with backoff instead of immediate repeated requests.

Platform/tool-specific checks

• Verify the command, editor, extension, or API client that produced the error.
• Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
• Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

1. Capture the exact error message and the command, editor action, or request that triggered it.
2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
3. Review the source evidence below and compare it with your environment.
4. Apply one change at a time and rerun the smallest failing action.
5. Keep the working fix documented for the team or deployment environment.

How to prevent it

• Keep provider/tool configuration documented.
• Record non-secret diagnostics such as tool version, provider name, model name, and command path.
• Add a lightweight check before CI or production workflows depend on the tool.

Sources checked

• https://github.com/openai/openai-python/issues/3054

Evidence note: Reported on openai-python#3054 (2026-04-03). Affects GPT-5.1/GPT-5.4 /responses endpoint under moderate concurrent load. 10-28% of requests receive no HTTP error, no timeout, no retry — TCP connection simply hangs. Critical production impact for paid API users. Category: OpenAI API (direct API endpoint error).

Related errors

• OpenAI API

FAQ

What should I check first?

Start with the exact /v1/responses endpoint silently drops 10-28% of concurrent requests under moderate load (5 simultaneous calls); TCP connection hangs indefinitely with no HTTP error or timeout text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed OpenAI API workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without /v1/responses endpoint silently drops 10-28% of concurrent requests under moderate load (5 simultaneous calls); TCP connection hangs indefinitely with no HTTP error or timeout.