| Error Code | Meaning |
|---|---|
| 400 | Invalid request: there was an issue with the format or content of your request. |
| 401 | Unauthorized: there's an issue with your API key. |
| 403 | Forbidden: your API key does not have permission to use the specified resource. |
| 404 | Not found: the requested resource was not found. |
| 429 | Your account has hit a rate limit. |
| 500 | An unexpected error has occurred internal to Anthropic's systems. |
| 529 | Your API is temporarily overloaded. |
When receiving a streaming response via SSE, it's possible that an error can occur after returning a 200 response, in which case error handling wouldn't follow these standard mechanisms.