Error 502: what to do when gpt-5.2 fails

A 502 means the gateway received an invalid response from the upstream model service: the request reached the gateway, but the hop to the upstream failed.

502 Bad Gateway means the gateway received an invalid response from the upstream model service. The request reached the gateway; the failure happened on the hop from gateway to upstream, usually due to an upstream restart or a dropped connection.

gpt-5.2 is served by OpenAI. Everything on this page — triggers, fixes and measured data — is compiled from the real runtime behaviour of this model at the gateway layer.

At this gateway, the most common trigger is: The upstream model service is unavailable or returned a malformed response. The recommended first action is: Retry once — 502s are usually transient.

Common causes

• The upstream model service is unavailable or returned a malformed response
• An upstream node is restarting
• The gateway-to-upstream connection was interrupted
• The model was temporarily taken offline

How to fix

• Retry once — 502s are usually transient
• Switch to an equivalent model from another vendor
• If only one model keeps returning 502, its upstream is unhealthy
• Try again later or contact us

Retry with exponential backoff

The snippet below retries when gpt-5.2 returns 502, up to 5 attempts, with an increasing wait plus random jitter so concurrent calls do not retry in lockstep. Read the base URL and API key from environment variables — never hardcode them.

import os, time, random
import requests

BASE  = os.getenv("OPENAI_BASE_URL")   # e.g. https://<your-gateway>/v1
KEY   = os.getenv("OPENAI_API_KEY")
MODEL = 'gpt-5.2'


def chat(messages, retries=5):
    """Retry with exponential backoff + jitter."""
    for i in range(retries):
        try:
            r = requests.post(
                BASE + "/chat/completions",
                headers={"Authorization": "Bearer " + KEY},
                json={"model": MODEL, "messages": messages, "stream": True},
                timeout=60,
            )
            if r.status_code == 429 or r.status_code >= 500:
                time.sleep(min(2 ** i + random.uniform(0, 1), 30))
                continue
            r.raise_for_status()
            return r.json()
        except requests.exceptions.Timeout:
            time.sleep(min(2 ** i + random.uniform(0, 1), 30))
    raise RuntimeError("gave up after " + str(retries) + " retries")


print(chat([{"role": "user", "content": "hello"}]))

Key facts for this model

FAQ

Other errors on this model

• gpt-5.2: error 429 — causes and fixes
• gpt-5.2: error timeout — causes and fixes
• gpt-5.2: error 500 — causes and fixes
• gpt-5.2: error 503 — causes and fixes
• gpt-5.2: error 504 — causes and fixes
• gpt-5.2: error 401 — causes and fixes
• gpt-5.2: error 403 — causes and fixes
• gpt-5.2: error 400 — causes and fixes

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• qvq-max
• qwq-32b
• glm-5
• MiniMax-M3
• kimi-k3
• hy3
• doubao-seed-evolving
• mimo-v2.5
• gpt-4o
• claude-opus-4-6

Back to the model page

Data updated: 2026-10-10 08:15