Record and replay¶

Recording and replaying a session

gentui http://localhost:8000/agent --record my_session   # chat as usual; quit when done
gentui --replay my_session                               # no backend needed

--record NAME works with any backend (a URL, an AgentCore ARN, or --demo). NAME becomes NAME.json in the current folder (--record runs/monday writes runs/monday.json, and the folder must exist). Gentui refuses to overwrite a file that is already there. The file is saved after every run and again when you quit.

Controls¶

Key / mouse	Does
`space` or the Pause / Play button	pause and play (at the end, it plays again from the start)
drag or click the bar	seek to any moment, forwards or back. `◆` marks where you sent a message
`←` / `→`	jump 5 seconds back / forward
`home`	back to the start
`+` / `-` or the speed button	0.5x, 1x, 2x, 4x, 8x
`t` or click a "Thought for 3s" block	open or close the chain of thought. `t` toggles all of them
`d`	show the raw AG-UI events
`q`	quit

Seeking backwards clears the chat and replays everything up to that moment, so it always matches what you saw live. Anything you opened or closed by hand is reset when you seek.

What is drawn¶

The replay feeds the recorded events to the same code that draws a live chat, so you get streamed Markdown, the chain of thought, every tool widget (commands and their output, tables, charts, the plan, memory lines, unknown tools as JSON cards) and the approval cards, which show the decision that was made (Approved, Approved with an edited command, Rejected). The buttons are disabled: a replay never sends anything.

Waits longer than 1.5 seconds (you thinking, a slow model) are squeezed to 1.5 seconds on the timeline, so a replay never sits idle. "Thought for Ns" and the time beside each message show the recorded time.

The file¶

{"format": "gentui-session", "version": 1, "gentui": "0.1.2", "recorded_at": "2026-10-09T10:15:00+01:00",
 "target": "http://localhost:8000/agent",
 "items": [
  {"t": 0.0,  "kind": "user",   "text": "what are the 5 largest files here?"},
  {"t": 0.41, "kind": "event",  "event": {"type": "RUN_STARTED", "threadId": "...", "runId": "..."}},
  {"t": 3.2,  "kind": "resume", "entries": [{"interruptId": "approve-c1", "status": "resolved", "payload": {"approved": true}}]}
 ]}

t is seconds since the recording started. kind is user (a message you sent), event (an AG-UI event exactly as the backend sent it), resume (your answer to an interrupt), submit (a widget's message on older backends) or new (/new).

Treat a recording like a log. It holds whatever the agent streamed, including tool output, so it can contain secrets or private data. Headers, tokens and your config are never written. Share recordings with care.