repository-history

# Repository History Recover historical constraints without inventing intent or blaming people. Produce a compact, cited history note before a risky edit. ## Ownership - Use this skill when the question is why a tracked file, symbol, line range, workaround, guard, migration, or compatibility behavior exists and how it changed. - Use [systematic-debugging](../systematic-debugging/SKILL.md) when the primary task is to reproduce and localize a current failure. History may supply a comparator after reproduction. - Use [diff-review](../diff-review/SKILL.md) for defects in an exact diff, [repository-review](../repository-review/SKILL.md) for a cross-cutting audit, and [technical-research](../technical-research/SKILL.md) for current external facts or API behavior. ## Authority and Evidence Boundary - Investigation is read-only. Do not fetch, pull, checkout, bisect with mutations, reset, rebase, amend, revert, delete refs, rewrite history, edit code, or contact an author unless the user separately authorizes that action. - Start from local Git objects. Query GitHub with `gh` only when remote discussion is material, the repository is in scope, and read-only network access is available. Never infer that a missing local commit or discussion does not exist when the clone is shallow or incomplete. - Never print raw remote URLs: they can embed credentials. List remote names with `git remote`; if host or repository identity is material, inspect the configured value only through a local...