participant.removed fires when a contact leaves or is removed from a group chat your agent is in.
Read the payload
Thedata object is the ParticipantRemovedEvent schema from the API contract. The envelope around it is the same on every event and is described in the event catalog.
Handle the event
Mark the handle as gone in your stored membership forchat_id; participant.status tells you whether they left or were removed. Anything your agent sends from now on does not reach them. If the departing handle is your own agent, stop working on that chat.

