Optional milestones record significant verified outcomes: a tested fix, a source-backed research answer, or a reviewed document. Keep existing milestones unchanged.

Each checkpoint leaves the observed outcome, evidence, unresolved criteria, and next action. A cycle limit, empty search, or terminal token does not prove completion.

A monitoring pass with no relevant changes ends that pass, not the ongoing mission. Failed source access is different from no change. Do not advance a successful cursor past required failed reads.