> ## Documentation Index
> Fetch the complete documentation index at: https://bianxieai.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Error handling

> HTTP status codes, rate limits, and retries

| Status    | Meaning and action                                                                                                       |
| --------- | ------------------------------------------------------------------------------------------------------------------------ |
| `400`     | Invalid parameters. Correct the request using the response `message`.                                                    |
| `401`     | The API key is missing, malformed, or no longer valid.                                                                   |
| `403`     | Insufficient balance or permissions. Check the account balance, key status, and model access.                            |
| `429`     | An upstream limit, risk control, or retry loop was triggered. Use `message` to identify RPM, RPD, TPM, TPD, IPM, or IPD. |
| `500`     | Unknown service error. Record the time and error details, then contact support.                                          |
| `503/504` | High load or upstream timeout. Retry later with exponential backoff; streaming may help conversational requests.         |

The platform does not impose a fixed rate limit by default, but upstream services, risk controls, and repeated failures can still return `429`.

If the issue persists, visit [Contact us](https://docs.bianxie.ai/en/faq/contact) for technical support and include the request time, endpoint, model ID, HTTP status, and complete `message`. Never send your full API key.