X-Firm-ID (auto-injected for firm API keys) or an optional firm_id query parameter.
Get halt state
operationId: getEmergencyHalt
Response — 200 OK
Activate halt
operationId: activateEmergencyHalt
Activates firm-wide halt and optionally enqueues sim-account liquidation. Returns an async job envelope.
Body
Response — 202 Accepted
Release halt
operationId: releaseEmergencyHalt
Releases an active halt and restores normal trading for the firm.
Response — 200 OK
Get halt job
operationId: getEmergencyHaltJob
Polls progress of an emergency halt background job.

