The exit code that belonged to the pipe

The verify command piped into tail printed exit=0 while the gate had failed. In a pipeline you get the last command's exit code, not the one that matters.

pnpm verify | tail printed exit=0. The gate had failed. tail succeeded, and in a pipeline the exit code you get is the last command’s.

The same defect has cost a commit here before, through git push | tail reporting success while a hook rejected the push.

It is a small thing that produces a specific and expensive failure: you believe you have verified something and move on. Run gates unpiped and read the code directly, or read PIPESTATUS. Never let a formatting command stand between you and the answer you are relying on.