Limited-Visibility Deployments — Callback APIs Callback APIs provide a structured channel for deployers to report events to the provider. Published webhook endpoints cover specific event types: performance degradation reports, incident notifications, user complaints, and ground truth feedback. Deployers call these endpoints when events occur. The API schema is predefined, documented in the Instructions for Use, and includes validation to ensure data quality. This mechanism depends on deployer cooperation; the deployer agreement includes an obligation to use the callback APIs and a defined SLA for reporting. The Technical SME monitors callback API usage: a deployer that stops calling the API may have disconnected from the monitoring framework, creating a blind spot. Callback APIs complement telemetry agents. Telemetry captures continuous quantitative data; callbacks capture event-driven qualitative information that automated metrics cannot detect (a deployer observing unusual operator behaviour, a complaint from an affected person, a deployment context change). Key outputs

• Published webhook endpoints per event type
• Predefined schema documented in Instructions for Use
• Contractual obligation with SLA for deployer reporting
• Complementary to telemetry agents for event-driven information