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Errors

The AutoRFP.ai API error format, what each HTTP status means, and how MCP reports failures differently from the REST API.

The REST API uses standard HTTP status codes. A failed request returns a JSON body with an errors array.

Error format

{
  "errors": [
    {
      "status": "401",
      "title": "invalid_token",
      "detail": "Missing Authorization: Bearer token"
    }
  ]
}

Each entry in errors has:

Field	Description
`status`	The HTTP status as a string.
`title`	A short name for the problem, for people to read.
`detail`	Optional. A human-readable explanation of how to fix it.
`code`	Optional. A machine-readable code for the specific failure.

Branch on status and, where present, code (for example INSUFFICIENT_SCOPE or RATE_LIMITED). Treat title and detail as text for people: their wording can change.

Status codes

Status	Meaning
`400`	Invalid request. Check the parameters and body.
`401`	The API key is missing or invalid.
`403`	The key does not have the scope the endpoint requires.
`404`	Not found, or the key’s Default User cannot access it.
`429`	Rate limited. Wait and retry later.
`500`	Server error. Retry later, and contact us if it persists.

Each endpoint in the reference lists the statuses it can return, including any extra ones specific to that endpoint.

Errors from the MCP server

The MCP server reports problems in two ways:

A tool call that fails, for example because the token lacks the scope or the item does not exist, returns a normal tool result with isError: true and a text message. It is not an HTTP error.
A missing or invalid token returns HTTP 401 with a WWW-Authenticate header, which MCP clients use to start the sign-in.

The MCP endpoint allows 600 requests per minute per IP address.