Change the execution tool

Define the task contract

Describe the task generically, without any real provider name:

{
  "operation": "schedule_session",
  "input_schema": { "topic": "string", "duration_minutes": "number" },
  "output_schema": { "session_reference": "string" },
  "permission_scope": "calendar.write",
  "approval_rule": "human_required",
  "timeout_ms": 8000,
  "retry_policy": "no_auto_retry",
  "audit_event": "session_scheduled"
}