Documentation Drift
Does documentation still predict behavior? A sensor of the gap between what the system is documented to do and what it actually does.
Documentation drift measures whether the docs match reality. When they diverge, the documentation becomes a liability: it misleads rather than guides. Detecting drift requires comparing documented behavior to observed behavior or test assertions.
Sensor properties
| Property | Value |
|---|---|
| Oracle strength | Low — drift is a risk factor, not a bug |
| Independence | High — docs and code are independent artifacts |
| Scope | Module-level |
| Feedback latency | Days |
| Actionability | Exploratory — shows the gap |
| Type | Retrospective |
What it cannot detect
Documentation drift can only be detected where documentation exists. Undocumented behavior is invisible to this sensor.