Thanks — I see you're asking why

participant.metadata

is empty after adding metadata on a SIP inbound trunk. You're right to expect that data to appear somewhere; the important distinction is where that data lives and how it's propagated. Short answer • Trunk-level metadata is NOT automatically copied into

participant.metadata

. That field must be set on the participant (via token or API) or you must map SIP headers into participant attributes. How to fix this (three options) 1. Map SIP headers to participant attributes ◦ Use the trunk's

headers_to_attributes

mapping so incoming SIP headers become

participant.attributes

. This is useful for caller ID, DNIS, or other header-based values. ◦ Note: those values appear on

participant.attributes

, not

participant.metadata

. 1. Set participant metadata when creating the participant/token ◦ Include metadata in the participant's token (use

setMetadata()

in the SDK) so

participant.metadata

is populated when they join. ◦ Or update the participant after join using the server API (

UpdateParticipant

) to set

metadata

. 1. Pass context via job/dispatch metadata (if using dispatch) ◦ If the data is part of the call context (for routing/agent jobs), provide it as job or dispatch metadata so the agent receives the structured context you need. What I recommend next • If the value originates from a SIP header, try option 1 and read it from

participant.attributes

. • If you want the value in

participant.metadata

, include it in the participant token or call

UpdateParticipant

after the participant joins. If you'd like, tell me: • Which specific field/value you set on the trunk (metadata or a SIP header), and • Whether you want that value available as

participant.metadata

or

participant.attributes

. I can then give the exact config snippet or the API/SDK call you'd need. Sources: How to do call transfers with Five9 | LiveKit | Server-side | livekit/livekit_composite | DeepWiki | server-sdk-kotlin | livekit/livekit_composite | DeepWiki | Agent dispatch | LiveKit Documentation