Failures are named where the Failed chip appears. Tiles render the worker error text in a Failed row; an open card in the decision state names a concurrent error inside the hero (answering resumes the worker) and always offers Open thread — no more unexplained chip.
Answering clears the interrupted turn's failure. Both live and recovered answer paths reset last_error, and an error arriving while a question is open is superseded at birth, so one card counts once in the badge and Needs attention.
Changed
Retry is a compact icon action on tiles. The wide labeled button left the heading; the error row carries an icon-sized ↻ at its right edge with a full accessible name. It renders only when a live thread on a non-terminal card can act — never a dead button on Done or thread-less cards.