> For clean Markdown of any page, append .md to the page URL. > For a complete documentation index, see https://docs.instabase.com/api-sdk/api-reference/response-statuses/llms.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.instabase.com/_mcp/server. # Response statuses > Review AI Hub API response classes. AI Hub API endpoints use HTTP status codes to communicate response statuses. Responses are grouped in the following classes: | Range | Response class | Notes | | ------------- | -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `100` ‑ `199` | Informational | | | `200` ‑ `299` | Successful | | | `300` ‑ `399` | Redirect | | | `400` ‑ `499` | Client error | - `401` indicates an [authorization](/api-sdk/authorization/) error. This can be caused by an invalid [API token](/api-sdk/authorization#oauth-tokens), an invalid [IB-Context header](/api-sdk/authorization#ib-context-header), or by calling an API that requires permissions you don't have. - `403` indicates insufficient consumption units to complete the call. | | `500` ‑ `599` | Server error | Something has gone wrong with the server. Try your request again later. | > **Note** > > Legacy APIs might not use the same response classes. > Review AI Hub API response classes.