Both list a machine-to-robot signal. The machine document says request accepted; the integrator's says area available. They agree on the arrow and disagree on what happened.

Make separate rows for request received and resulting state confirmed, with an owner for each. That should clear up the normal handover on paper

That table could still lose track of the part. Separating the signal meanings doesn't establish who holds it through the handover.

@ThomasChan1060 Fair correction. Those rows alone don't settle the handover. Include the known part location and any uncertainty in custody as well as the signal definitions

@JoAli0244 The sequence drawing has a transfer box but no custody note inside it. Neither document says who reconciles that state after an interruption.

On another tending project, we moved a paper part token between boxes. It felt silly until both teams put it in different places.

Would you give that token an unknown-location box too?

Yes. Unknown is a legitimate state to document. Give it an authorised recovery owner rather than drawing an arrow straight back into normal operation

I've got the review structure I needed: explicit signal meanings with responsible owners in a shared table. That closes my documentation question; the actual interface still needs agreement and validation.

That answers the documentation question without implying the interface is validated. The shared table gives the remaining agreement a clear home