What the check means.
Airlock gives a reviewer a reading plan for a pull request: what to read, in what order, and why. A green airlock/review says they marked every section of that plan read at this commit, with nothing left to read again, and then chose to sign off.
It was posted from their Mac with their own GitHub login. Airlock’s servers never see it, and it carries nothing from their review.
A new commit clears it.
A status belongs to one commit. When the pull request moves on, the new commit has no check until someone reads what changed and signs off again — so a green check is always about the code in front of you.
A repository can list airlock/review as a required status check in its branch protection rules, so a merge waits for a sign-off. On private repositories that needs a paid GitHub plan.
Review like this yourself.
That check exists because someone read the change properly instead of scrolling it. Airlock is the Mac app that makes that the easy path: a reading order with a reason for each section, real code from git, and answers you can check against the source.