Supervisor tools error codes (mpbx-b2bua, mpbx-api)

Returned by the supervisor tools of the call engine (B2bua::supervise, supervise_mode, supervise_stop, drop_queue_call; W6-CC-04) and by their REST routes under /api/v1/supervisor/.... When the supervisor's own device cannot be rung, the originate codes of calls.md (MPBX-CALL-DEVICE-UNAVAILABLE, MPBX-CALL-BUSY, ...) pass through. A permission refusal is MPBX-RBAC-FORBIDDEN (auth.md). Messages never contain numbers, names or SIP identifiers. Guide: Supervisor tools.

Code	Kind	Meaning	What to do
MPBX-SUP-CALL-NOT-FOUND	not_found	No live call with this id in the company (a call of another company is never found), or the call ended while the request ran.	Refresh the panel; the call may have ended.
MPBX-SUP-NOT-QUEUE-CALL	permission_denied	The call is not a queue call answered by an agent, the agent has left it (transferred), or it is a call of another queue than the one the permission was checked for. Supervisors only ever reach the calls of their queues.	Supervise calls from the queue panel.
MPBX-SUP-FORBIDDEN	permission_denied	An emergency call (never supervised), a call the supervisor is a party of, or a mode change by another supervisor than the one who joined.	Leave emergency calls alone; only the supervisor who joined switches its mode.
MPBX-SUP-STATE	conflict	The call is not answered or is ending; it is in a transfer, a park, an app or a conference; another supervisor is on it already. For a mode change or a stop: the call is not supervised.	Wait for the other operation to end, or for the other supervisor to leave.
MPBX-SUP-UNSUPPORTED	unavailable	This engine runs no media app with conference rooms, or the media app cannot whisper to the agent (no participant ids).	Wire mpbx-media into the engine (mpbx run does).
MPBX-SUP-MEDIA	unavailable	mpbx-media did not create the room or a participant, did not change the supervisor's audio, or a leg's re-INVITE failed. Nothing changed: the call stays as it was.	Retry; check mpbx-media and the phones.
MPBX-SUP-ENGINE-UNAVAILABLE	unavailable (503)	This API server has no call engine (an API-only node, or the SIP side is off). The panel still answers, with live: false.	Use a node that runs the engine (roles = all).
MPBX-SUP-AGENT-NOT-FOUND	not_found	PUT /supervisor/agents/{extension_id}/login: the extension is not an agent of any queue of the company.	Check the extension id on the panel.