upstream_timeout: the target did not answer in time

Common causes

• The target is slow or under load and takes longer than your timeout_ms.
• timeout_ms was set below what the endpoint realistically needs.
• The target streams a response indefinitely instead of returning a body.

How to fix it

1. 01Raise timeout_ms for endpoints you know are slow — the ceiling is 30 seconds.
2. 02Retry with backoff: unlike validation failures, a timeout may succeed on a second attempt.
3. 03For long-lived streams use a socket ticket rather than a forward.

What it looks like

{
  "ok": false,
  "error": { "code": "upstream_timeout", "message": "..." },
  "meta": { "duration_ms": 15000, "target_host": "api.example.com" },
  "quota": { "remaining": 4998, "unit": "trips" }
}

Every error code