# unauthenticated

HTTP 401 · Requests and sign-in (SPEC §15.3, §20.1)

Sign in or send a valid token in the Authorization header.

## Does retrying help?

Not as it is. Change the request as the message says, then send it again.

## The response

Every Flatstack error has this shape. `details`, when present, says more about this case.

```json
{
  "error": {
    "code": "unauthenticated",
    "message": "Sign in or send a valid token in the Authorization header.",
    "docsUrl": "https://flatstack.dev/docs/errors/unauthenticated"
  }
}
```

[All error codes](/docs/errors)