Codex mechanism (20dafe201d91d4405eef05ecd1db0257f13a9ac8)
- one event-owned status row adjacent to the composer
- width-bounded label
- absent when no task is running

Claude Code mechanism (2.1.219, 7006c4c3acac98e554d3997baeda6a7fa4d1ff7c)
- activeForm preferred for current task wording
- bounded horizontal activity summary
- short completion-feedback hold

Pi constraints
- canonical goal/task/lane truth
- semantic theme tokens
- explicit expansion for detail
- no replay of terminal state on resume
- no human UI routing in worker sessions