The Agent tool runs subagents in the background, so the parent's result arrives at launch while the subagent works on for minutes; finishing on it read a running agent as finished with a transcript cut off at launch. A subagent now ends on its own message_delta end_turn, and a later line for a finished one reopens it, since a background agent can be messaged again. The card's expander row was only the chevron's height, so a tap for it landed on the first subcard; it is the platform's 48dp minimum now. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>