The transcript is the record of what an agent did on your machines. It should outlive the tab.
Every session — including those the rail no longer shows — lives on a conversations page, narrowed four ways: by age, by machine, by tag, and by state.
Search that tolerates half-memory
Full-text search across every conversation, fuzzy enough to survive half-remembered wording. It indexes the prompts and the reply immediately before each one, rather than every line of tool output, so results are the conversation rather than the noise.
Archive and delete are different things
Archive puts a conversation away and keeps all of it. Delete destroys the transcript, and is never the default action.
Organising
Notes, colours, tags, pinning and drag-to-reorder. Per-session drafts survive a page reload, so a half-written message is still there when you come back.