Session Replay
Play back an agent session step by step — its structure, timeline, and decisions — as a guided replay.
Experimental. Session Replay is under active development and its behavior may change. Today one trace maps to one session; richer multi-trace sessions are in progress.
Where Traces show one run as a span tree, Session Replay turns that run into a player you can step through — watching the agent's structure unfold, where time went, and what each step decided, in order. It lives on the Sessions page.
Sources
The replay player runs against two kinds of input:
- Live — real traces from your project. Pick a run and replay it.
- Demos — bundled, synthetic example architectures so you can see how different agent shapes replay before pointing it at your own data:
- Parallel fan-out — steps that run concurrently
- ReAct loop — reason → act → observe cycles
- Hierarchical delegation — an agent delegating to sub-agents
- Multi-turn session — several turns of one conversation
The player
A persistent shell wraps every replay, with a hero view in the center that you can switch:
- Transport — playback controls to step or play through the session.
- Structure graph — the shape of the run (who called what).
- Timeline — each step on a time axis, so concurrency and idle gaps are visible.
- Inspector — the selected step's details (inputs, outputs, attributes).
Two center views:
- Story — a narrative walkthrough of the session, step by step.
- Tree — a proportional delegation tree alongside a gantt of the run.
Where to find it
Open Sessions in the sidebar to use the full player, or open a trace and use its embedded replay to step through that single run in place. Because replay reads the same span data as Traces, anything captured by your instrumentation shows up here with no extra setup.