What probably matters to youSection of the release
What
A hook can now carry a matcher written in permission rule syntax, so it only fires when the tool call matches. Non-matching commands no longer spawn the hook process at all, which cuts startup cost on hooks that previously ran and immediately exited.
Details
The field is documented as permission rule syntax, the same form used for permission allow and deny rules.
The stated benefit is avoiding hook spawns for commands the hook would ignore.
Evidence
Only runs if the tool call matches the pattern. Avoids spawning hooks for non-matching commands.
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
