> ## Documentation index > Fetch the complete documentation index at: https://upstash.com/docs/llms.txt > Ask it with GET https://upstash.com/docs/ask?q=. Short keywords rank best. > Use these to discover all available pages before exploring further. > Feature requests: https://upstash.com/docs/common/help/feature-requests.md lists what users asked for and how to vote for a request or add one. > Page rating: `GET https://upstash.com/docs/feedback?path=/docs/devops/developer-api/http_status_codes&helpful=true` (or `false`) records whether this page helped. An optional `comment` (URL-encoded, at most 500 characters) says what was missing or wrong. It is anonymous and needs no key. Comments hold no code, secrets or personal data. # HTTP Status Codes > The Upstash API uses the following HTTP Status codes: | Code | Description | | | ---- | ------------------------- | ------------------------------------------------------------------------------- | | 200 | **OK** | Indicates that a request completed successfully and the response contains data. | | 400 | **Bad Request** | Your request is invalid. | | 401 | **Unauthorized** | Your API key is wrong. | | 403 | **Forbidden** | The kitten requested is hidden for administrators only. | | 404 | **Not Found** | The specified kitten could not be found. | | 405 | **Method Not Allowed** | You tried to access a kitten with an invalid method. | | 406 | **Not Acceptable** | You requested a format that isn't JSON. | | 429 | **Too Many Requests** | You're requesting too many kittens! Slow down! | | 500 | **Internal Server Error** | We had a problem with our server. Try again later. | | 503 | **Service Unavailable** | We're temporarily offline for maintenance. Please try again later. |