Create or schedule an operational event message
Requires messages:write, a production studio credential with an exact active studio grant, owner/admin authorization, and Idempotency-Key. Transactional alert emails never contain the freeform body.
Authorizations
Batch Relay scoped API key or an anonymous Test Mode session. Scope names document required capabilities. Anonymous sessions are sandbox-only and do not authorize studio, event, billing, or Live Mode operations.
Headers
1 - 200Untrusted optional analytics hint naming the calling client surface. It never affects authorization, routing, pricing, or behavior.
1 - 100Untrusted optional analytics hint naming the calling client version. It never affects authorization, routing, pricing, or behavior.
1 - 100Untrusted optional analytics hint naming the invocation mode. It never affects authorization, routing, pricing, or behavior.
1 - 100Path Parameters
Stable public studio ID beginning with stu_. The API never selects a studio implicitly; a local CLI profile name is not a studio ID.
5 - 256^stu_[A-Za-z0-9_-]+$Body
Plain operational text; URLs and promotional content are rejected.
1 - 2000120photo_day_reminder, schedule_changed, location_changed, what_to_bring, event_canceled, general_operational, custom_operational Reserved for a future verified-contact release. V1 accepts only an empty array.
Accepted only for custom_operational.
120Response
Durable message command
Classification only in V1; authored notices still respect the guardian routine-message preference until an event change can be corroborated server-side.
routine, critical x >= 0Returned only from an authorized message-detail read.
x >= 0x >= 0x >= 0x >= 0x >= 0x >= 0