Hi everyone, I’m running into a strange issue when working with the Assistants API and wanted to check if anyone else has experienced this or found a solution. I’m sending a message to an existing thread using: 5:{"threadId":"thread_BZp7o5emhYRuGexN4j8N3JgJ","messageId":"msg_ujHzpWmArfLKpJN4wu90r…

I’m having the exact same problem and response status. It started last night (November 25, 2025) (GMT-5) and is still happening today (November 26, 2025). I still haven’t been able to figure out what’s going on.

Same here – I’m seeing this issue both in our apps and directly in the Assistants Playground. For me, streaming cuts off as soon as a response takes longer than about 15 seconds, but anything faster than that finishes normally. I have tested this with several different models and get the same resu…

Thank you, I can confirm that we are now not seeing this error. Havent tested everything but normal assistant messages, vector store and code interpreter work as before

Hi, The timeout increase has definitely helped — we’re now getting noticeably longer responses. However, the stream is still being reset abruptly with INTERNAL_ERROR on some runs. You can reproduce the issue directly in the API Playground. Example thread: thread_iUa3AJIcZ0uEs6vZSI351Oga [image] …

Even though timeout increase has helped, usually our assistants take more than 60 seconds (new timeout) to generate the data we need so we are still experiencing the same issue.

60 seconds is still too low for our use case. Is there any chance we get get this bumped back up to what it was?

Thanks all for the context - just shared with my team to review next week!

This has been updated (as of ~Nov 28)! Please let me know if you're still running into any timeout errors and thank you all for the feedback.

“Premature close” when sending messages to Assistants API threads?

API Bugs

OpenAI_Support November 26, 2025, 10:31pm 4

Hi everyone, sorry about this disruption. We increased the timeout on the backend so you shouldn't see this error for streaming requests. It may take a few minutes for the fix to be fully deployed. Let us know how things look for you!

Stream Interruptions Occurring During Assistants API Responses

Error Internal Server Error: The response ended prematurely. (ResponseEnded)

[Assistants API] Issue with gpt-4o: httpx.RemoteProtocolError: peer closed connection without sending complete message body (incomplete chunked read)

Assistants API Streaming Connection Closure Issue

Topic		Replies	Views
Stream Interruptions Occurring During Assistants API Responses API assistants-api	3	468	November 26, 2025
Error Internal Server Error: The response ended prematurely. (ResponseEnded) API gpt-4 , bug , assistants-api	2	636	November 26, 2025
[Assistants API] Issue with gpt-4o: httpx.RemoteProtocolError: peer closed connection without sending complete message body (incomplete chunked read) API assistants-api , gpt-4o	12	797	November 26, 2025
Assistants API Streaming Connection Closure Issue Bugs bug , error , assistants-api , streaming	5	415	November 26, 2025
200 OK from /v1/responses but body times out (UND_ERR_BODY_TIMEOUT) Bugs api , gpt	29	1313	February 16, 2026

“Premature close” when sending messages to Assistants API threads?

Related topics