Observe
Establish actual state through bounded measurement, inspection, or read-only collection, rather than assuming a command or a declared configuration reflects reality.
Identification
Diagnostic questions
- What is actually true now?
- What evidence supports that conclusion?
- What is directly observed, what is inferred, what is cached, and what is unknown?
- Does observing this change it?
In practice
Observation shows up wherever a system’s picture of the world could drift from the world. HA Light Controller reads a light’s achieved state after commanding it, because the command and the result are different facts. RepoLens collects evidence into immutable snapshots so a later claim about a repository can be checked against what was actually there.
The discipline is less about collecting more and more about labelling what you have. A value that is measured, a value that is inferred, and a value that is stale are three different things, and a system that renders them identically has quietly stopped observing.
Background threads
Watch-standing is observation as a job. A gauge reading is not the plant’s state; it is one input, taken with a known instrument, at a known time, with a known way of being wrong. Equipment breakdown work adds the other half: an inspection finding is only as good as the record of what was inspected and when.
Common failure
Treating a successful command as a confirmed result. The log says the change was sent; nobody looked to see whether it landed.