Feature Flag Exposure Telemetry
A change behind a flag is not a change anyone has experienced. Flag evaluation streams answer “who is actually seeing the new behavior, right now?” — the difference between deployed and live, and the ground truth underneath every canary analysis claim about a rollout’s state.
Sensor properties
| Property | Value |
|---|---|
| Oracle strength | High — evaluation events are direct records of what each request saw |
| Independence | High — emitted by the flag infrastructure, not the feature code |
| Scope | System |
| Feedback latency | Seconds |
| Actionability | Guiding — tells you the true exposure of a change |
| Type | Retrospective |
What it cannot detect
Whether the new behavior is correct — only where it is active. Exposure is the denominator; behavioral evidence still has to come from synthetic monitoring or real traffic.