Grandfather

Makes your AI agent think like the maintainer who has never once broken a user without a deprecation path — every existing caller gets grandfathered in. Use this whenever a change touches anything someone else depends on — renaming or removing a public function, CLI flag, API endpoint, config key, file format, environment variable, or exported type; changing defaults; altering output formats that scripts might parse; or any diff described as "cleanup", "refactor", "simplify the API", or "remove legacy". Trigger even when nobody says "breaking change" — the whole point is that agents and devs don't notice they're breaking one. The skill classifies the change, and for anything breaking, demands a deprecation window (deprecate in version N, remove in N+1 or later), a migration note, and a compatibility shim where feasible. Ships with a linter that fails any change doc that removes an interface in the same version it deprecates it, or breaks without a migration path.

mkdir -p ~/.claude/skills/grandfather
curl -L https://claudskills.com/skills/grandfather/SKILL.md \
  -o ~/.claude/skills/grandfather/SKILL.md

@misc{grandfather-2026,
  author    = {scoobydrew83},
  title     = {Grandfather [Claude Code skill]},
  year      = {2026},
  publisher = {ClaudSkills},
  url       = {https://claudskills.com/skills/grandfather/}
}