Our API follows a predictable HTTP error code format:
400 - invalid_request_error: There was an issue with the format or content of your request. We may also use this error type for other 4XX status codes not listed below.
401 - authentication_error: There’s an issue with your API key.
403 - permission_error: Your API key does not have permission to use the specified resource.
404 - not_found_error: The requested resource was not found.
413 - request_too_large: Request exceeds the maximum allowed number of bytes.
429 - rate_limit_error: Your account has hit a rate limit.
500 - api_error: An unexpected error has occurred internal to Anthropic’s systems.
529 - overloaded_error: API is temporarily overloaded.