openrouter-common-errors

# OpenRouter Common Errors ## Overview OpenRouter returns standard HTTP error codes plus OpenRouter-specific error codes in the response body. The most common: 401 (auth), 402 (credits), 429 (rate limit), 400 (bad request), and 5xx (upstream provider errors). Each error includes a `code` field and a human-readable `message`. This skill covers every common error, its root cause, and the exact fix. ## Complete Error Reference | HTTP | Error Code | Cause | Fix | |------|-----------|-------|-----| | 400 | `bad_request` | Malformed request body | Validate `messages` array format; ensure model ID includes provider prefix | | 400 | `invalid_model` | Model ID not found | Check model exists: `curl -s https://openrouter.ai/api/v1/models \| jq '.data[].id'` | | 400 | `context_length_exceeded` | Prompt + max_tokens > model limit | Reduce prompt size or use a larger-context model | | 400 | `invalid_tool_schema` | Tool definition has unsupported types | Use basic JSON Schema types only (string, number, boolean, object, array) | | 401 | `invalid_api_key` | Key malformed, revoked, or wrong | Regenerate at [openrouter.ai/keys](https://openrouter.ai/keys); key must start with `sk-or-v1-` | | 401 | `missing_api_key` | No `Authorization` header | Add `Authorization: Bearer sk-or-v1-...` header | | 402 | `insufficient_credits` | Credit balance is zero | Top up at [openrouter.ai/credits](https://openrouter.ai/credits) | | 402 | `credit_limit_reached` | Per-key credit limit hit | Increase key l...