> Fetch clean Markdown by appending `.md` to any page URL under https://signalwire.com/docs or requesting it with the HTTP header `Accept: text/markdown`. The root index at https://signalwire.com/docs/llms.txt lists the available documentation indexes. # addressId$ > Observable of the participant's address ID. ```ts get addressId$(): Observable ``` Observable of the participant's address ID. ## addressId ```ts get addressId(): string | undefined ``` Address ID of this participant, or `undefined` if not available. ## **Examples** ```ts participant.addressId$.subscribe((addressId) => { console.log('addressId:', addressId); }); ``` > Observable of the participant's address ID.