How to hand off an automation project so the client can maintain it

I used to think an automation project was done when the workflow ran successfully three times in a row. That was fine until the client changed a column name, the script failed, and nobody on their side knew what was safe to touch. Now I treat handoff as part of the build. The client gets a short runbook with where the inputs live, what the normal output looks like, what common errors mean, and wh…