Thanks — I’ll answer your question about setting room metadata when issuing a LiveKit auth token. Short answer • You cannot set room metadata directly inside a LiveKit auth token once a room already exists. • You can include a RoomConfiguration in the token to set initial metadata only when the room is created at first join. • To change metadata for an existing room, call the server-side API (

updateRoomMetadata

) after creation. How to set initial room metadata when creating a room via token 1. Create an AccessToken and grant

roomJoin

for the room. 2. Attach a

RoomConfiguration

to the token and set

metadata

to the desired initial value. 3. Issue the JWT. If the room does not yet exist, the room will be created with that metadata. Node.js example:

const at = new AccessToken(apiKey, apiSecret);
at.identity = 'user-identity';
at.addGrant({ roomJoin: true, room: 'my-room' });

at.roomConfig = new RoomConfiguration({ metadata: 'room-initial-metadata' });

const token = await at.toJwt();

Python example:

token = AccessToken(api_key, api_secret)
token.identity = "user-identity"
token.add_grant(room_join=True, room="my-room")

token.room_config = RoomConfiguration(metadata="room-initial-metadata")

jwt = token.to_jwt()

How to update metadata after the room exists • Use the server SDK’s room update API (for example

updateRoomMetadata

) to set or change metadata for an existing room. • Metadata updates are propagated asynchronously; clients receive

room_metadata_changed

events. When to use which approach • Use token-embedded

RoomConfiguration

only to set initial metadata at room creation time. • Use the server API to update metadata for existing rooms or to change metadata later. If helpful, tell me: • Are you trying to set metadata only at room creation, or update metadata for an existing room? • Which server SDK (Node, Python, Go, etc.) are you using? I can share exact code for that SDK. Sources: server-sdk-kotlin | livekit/livekit_composite | DeepWiki | Handling asynchronous metadata updates in LiveKit | LiveKit | server-sdk-js | livekit/livekit_composite | DeepWiki