# `room_type_unknown`

A Multiplayer API error, sent with HTTP 400. Status: the Multiplayer API is in private alpha; this code is part of its published contract.

## When

The request names a room type this project does not have.

## What to do

Use one of the room types in your project's config (GET /v1/config lists them), or add the type first.

## The answer

Every error is a JSON body with a stable `error` code. Clients act on the codes they know and treat any other code as a failure of its HTTP status, and keep fields they do not know.

```json
{
  "error": "room_type_unknown",
  "detail": "A sentence that is safe to show.",
  "next": "Use one of the room types in your project's config (GET /v1/config lists them), or add the type first.",
  "docsUrl": "https://lobbylab.gg/docs/errors/room_type_unknown"
}
```

See also: [every error code](/docs/errors), [the API reference](/docs/api) and [the docs](/docs).