xAI API

xAI API errors and fixes

18 xAI API errors from the official error docs, grouped by HTTP status, each with what it means, why it happens, the documented fix and whether to retry. Verified October 18, 2026.

HTTP 400 Bad Request

400 Bad RequestReturned on all endpoints when the request is invalid. The docs list an invalid argument in a POST body, an invalid URL param on a GET dynamic route, or an incorrect API key as causes.Retry? Not stated

HTTP 401 Unauthorized

401 UnauthorizedReturned on all endpoints when no authorization header or an invalid authorization token was provided.Retry? Not stated

HTTP 403 Forbidden

403 ForbiddenReturned on all endpoints when your API key or team lacks permission for the action, or the key or team is blocked.Retry? Not stated

HTTP 404 Not Found

404 Not FoundReturned on all endpoints when the model named in a POST body was not found or the endpoint URL is invalid.Retry? Not stated

HTTP 405 Method Not Allowed

405 Method Not AllowedReturned on all endpoints when the HTTP method is not allowed, for example sending a POST to an endpoint that only supports GET.Retry? Not stated

HTTP 415 Unsupported Media Type

415 Unsupported Media TypeReturned on endpoints supporting POST when the POST body is empty or the JSON content-type header is missing.Retry? Not stated

HTTP 422 Unprocessable Content

422 Unprocessable EntityReturned on endpoints supporting POST when a field in the POST request body has an invalid format.Retry? Not stated

HTTP 429 Too Many Requests

429 Too Many RequestsReturned on inference endpoints when you send requests too frequently and reach your rate limit. Each team has per-model limits on requests per second (RPS) and tokens per minute (TPM), set by a spend-based tier, and exceeding any limit returns 429.Retry? Yes

No HTTP status

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