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Compare mode

Compare mode runs one prompt across several lanes at once, each with its own model and sampling config, and streams the results side by side. Use it to compare models or settings such as temperature 0.2 and 1.2.

Open it from any Workbench chat: use the Single / Compare toggle in the composer. (The old …/workbench/<chat>/compare link still works — it redirects you into the chat with Compare mode active.)

1. Set it up

  1. Type your prompt once at the top — it's shared by every lane.
  2. Each lane has its own model picker and full sampling config: max tokens, temperature, top_p / top_k / min_p, the presence / frequency / repetition penalties, seed, and stop.
  3. Duplicate a lane to compare the same model at different settings, or add more lanes for more models (up to 6).

2. Run

Click Run all to start every lane, or the per-lane Run to start one. Lanes stream independently and side by side — a slow or cold lane doesn't hold up the others. Stop all cancels everything in flight. Running compare does not touch your single-pane chat history.

3. Saved runs

Every Run all is saved automatically as a snapshot. A compare-run history list appears at the bottom of the pane, newest first — each row shows the timestamp, the shared prompt, and the lane count; expand a row to see the per-lane model chips. Click Restore to reload that run, including its lanes, prompt, and stored completions. The most recent 20 runs are kept per chat; older ones are removed.

4. Heatmap

Toggle Heatmap on a lane (and choose how many alternatives to record) to colour each token by probability — green = confident, red = surprising — using the same colour ramp as the Loom. Hover a token to see the top alternatives the model considered.

5. Billing

All lanes bill to one API key (the chat's key, or your default). Each lane is a separate generation, so a 4-lane run counts as 4 generations against your usage and budget.

Cold starts

Always-on models respond immediately. Putting an on-demand large model (e.g. 405B) in a lane triggers a cold boot for that lane — it will sit "warming up" for a few minutes before tokens appear, while your other lanes stream normally. See Cold-boot waiting.