Hi,
I’m experiencing an issue where a prompt (~27,776 input tokens) consistently hangs when executed in our cloud environment. The request rarely returns a response, and when it does, it takes approximately 6 minutes.
The same prompt works reliably on my local machine every time. I initially used the OpenAI Python client with LangChain, but after encountering the issue I tested using a raw curl request and observed the same hanging behavior. When I run the exact same prompt with gpt-4.1, it works without any problems.
This suggests the issue may be specific to gpt-5 handling large-token requests in the cloud.
Thank you.
curl -v -X POST "https://api.openai.com/v1/responses" \
--max-time 900 \
-H "Content-Type: application/json" \
-H "Authorization: Bearer $OPENAI_API_KEY" \
-d @payload.json \
2>&1 | tee curl_debug.log
Note: Unnecessary use of -X or --request, POST is already inferred.
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:-- 0
* Host api.openai.com:443 was resolved.
* IPv6: (none)
* IPv4: 162.159.140.245, 172.66.0.243
* Trying 162.159.140.245:443...
* Connected to api.openai.com (162.159.140.245) port 443
* ALPN: curl offers h2,http/1.1
} [5 bytes data]
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
} [512 bytes data]
* CAfile: /etc/ssl/certs/ca-certificates.crt
* CApath: /etc/ssl/certs
{ [5 bytes data]
* TLSv1.3 (IN), TLS handshake, Server hello (2):
{ [122 bytes data]
* TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8):
{ [19 bytes data]
* TLSv1.3 (IN), TLS handshake, Certificate (11):
{ [2534 bytes data]
* TLSv1.3 (IN), TLS handshake, CERT verify (15):
{ [79 bytes data]
* TLSv1.3 (IN), TLS handshake, Finished (20):
{ [52 bytes data]
* TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1):
} [1 bytes data]
* TLSv1.3 (OUT), TLS handshake, Finished (20):
} [52 bytes data]
* SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384 / X25519 / id-ecPublicKey
* ALPN: server accepted h2
* Server certificate:
* subject: CN=api.openai.com
* start date: Nov 14 00:26:50 2025 GMT
* expire date: Feb 12 01:26:48 2026 GMT
* subjectAltName: host "api.openai.com" matched cert's "api.openai.com"
* issuer: C=US; O=Google Trust Services; CN=WE1
* SSL certificate verify ok.
* Certificate level 0: Public key type EC/prime256v1 (256/128 Bits/secBits), signed using ecdsa-with-SHA256
* Certificate level 1: Public key type EC/prime256v1 (256/128 Bits/secBits), signed using ecdsa-with-SHA384
* Certificate level 2: Public key type EC/secp384r1 (384/192 Bits/secBits), signed using ecdsa-with-SHA384
} [5 bytes data]
* using HTTP/2
* [HTTP/2] [1] OPENED stream for https://api.openai.com/v1/responses
* [HTTP/2] [1] [:method: POST]
* [HTTP/2] [1] [:scheme: https]
* [HTTP/2] [1] [:authority: api.openai.com]
* [HTTP/2] [1] [:path: /v1/responses]
* [HTTP/2] [1] [user-agent: curl/8.5.0]
* [HTTP/2] [1] [accept: */*]
* [HTTP/2] [1] [content-type: application/json]
* [HTTP/2] [1] [authorization: Bearer __KEY_MASKED__]
* [HTTP/2] [1] [content-length: 121619]
} [5 bytes data]
> POST /v1/responses HTTP/2
> Host: api.openai.com
> User-Agent: curl/8.5.0
> Accept: */*
> Content-Type: application/json
> Authorization: Bearer __KEY_MASKED__
> Content-Length: 121619
>
} [5 bytes data]
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
{ [238 bytes data]
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
{ [238 bytes data]
* old SSL session ID is stale, removing
{ [5 bytes data]
* We are completely uploaded and fine
{ [5 bytes data]
100 118k 0 0 100 118k 0 226 0:08:58 0:08:56 0:00:02 0< HTTP/2 502
< date: Mon, 08 Dec 2025 16:04:15 GMT
< content-type: text/plain; charset=UTF-8
< content-length: 15
< strict-transport-security: max-age=31536000; includeSubDomains; preload
< x-content-type-options: nosniff
< x-frame-options: SAMEORIGIN
< referrer-policy: same-origin
< cache-control: private, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0
< expires: Thu, 01 Jan 1970 00:00:01 GMT
< set-cookie: _cfuvid=XXXXXX; path=/; domain=.api.openai.com; HttpOnly; Secure; SameSite=None
< server: cloudflare
< cf-ray: 9aad7240fed09712-AMS
< alt-svc: h3=":443"; ma=86400
<
{ [15 bytes data]
100 118k 0 15 100 118k 0 226 0:08:58 0:08:56 0:00:02 3
* Connection #0 to host api.openai.com left intact
error code: 502