wire-it-when-you-write-it

Ship a mechanism and its caller in the same change, and add the check that fails when a caller disappears — never leave a tested module, script, or gate that nothing invokes. Use when creating any new script, module, hook, workflow, or check, and when reviewing a change that adds one. Not for deciding whether a tool should exist at all (mechanize), whether a tool's verdicts can be trusted (verify-the-instrument), or whether to adopt an existing tool instead of writing one (adopt-or-build) — this is only about the gap between writing a mechanism and something actually calling it.