SYSE.36:4.2 - Separate measurement meaning from implementation

Write the service-level indicator, SLI, specification in terms of the user outcome before choosing a counter or query. Then identify how the available instrumentation could observe that specification and where it would miss or distort it.

For an event-ratio indicator, define both good events and eligible events over the same population and interval. For a time-based indicator, define the evaluated periods and their conditions. Do not combine request counts, user minutes and task outcomes in one ratio without a justified measurement Method.

If the important semantic result is not observable, return that gap. An easier proxy may still be reported under its own narrower meaning, but it cannot silently replace the required result. A dependency-health result provides evidence about the conditions checked on that dependency; an HTTP success status shows that the server reported success.