Does anyone know the correct payload structure for updating participant attributes via the Conversations API while a WebRTC session is active? My Electron renderer process attempts a PATCH request to /api/v2/conversations/voice/{id}/participants/{id} using the standard SDK token.
The request returns a 409 Conflict error immediately. The JSON body includes only {"attributes": {"key": "value"}} without modifying the participant role or status. I have verified the conversationId matches the active session.
Is this endpoint restricted to post-call interactions? I need these attributes to persist for downstream analytics during the active call leg. The SDK documentation is silent on mid-call attribute mutations.