Introducing Synthesis, Compare, and Debate: Three Ways Deepest Resolves Every Answer

The smartest people don't use one AI — they use all of them, and then they check where the models disagree. We built Deepest around that idea. Today we're shipping three distinct ways to bring every model's answer together: Synthesis, Compare, and Debate. The last one makes the models argue with each other until they converge.

What changed

When you ask Deepest a question, it sends your prompt to every model you've selected and they all answer at once. The interesting part has always been what happens next — how you turn several strong-but-different answers into one you can act on. Until now, Deepest did one thing there: it combined the responses into a single best answer.

That's still the default, and we've given it a clearer name. What used to be called "Deepest summary" is now Synthesis — because "summary" undersold it. It isn't shortening anything; it's merging the best reasoning from every model into one comprehensive answer. The word now matches the work.

Alongside it, we've added two more modes. You pick which one you want per question, right in the prompt bar.

Synthesis: one best answer

Synthesis is the everyday mode. It reads every model's response and writes a single, comprehensive answer that pulls the strongest points from each. When four models all tell you the same thing, that's a high-confidence signal — and Synthesis surfaces it as one clean answer instead of four overlapping ones you have to reconcile yourself.

Reach for it when you just want the best answer to a question and don't need to see the seams. Most of the time, that's what you want.

Compare: where they agree and disagree

Synthesis quietly throws away the single most valuable thing a multi-model tool can tell you: where the models disagree. When GPT, Claude, and Gemini all reach the same conclusion, you can trust it. When they split, that's exactly the moment to slow down — and no single-model tool can ever show you that, because it only has one opinion.

Compare mode makes the disagreement the point. It lays out:

• Where they agree — the points every model converges on, which you can treat as higher-confidence.
• Where they disagree — the contested points, with each model's position attributed by name, and a short explanation of why they split: genuine uncertainty, different assumptions, or a known tendency of a particular model.
• For and against — a plain trade-off breakdown for decision-type questions, so you can decide for yourself instead of being handed one answer.

Use Compare for judgment calls and high-stakes decisions — the kind where being handed a single confident answer is exactly the wrong thing. It's the anti-sycophancy view: it won't paper over a real split to sound authoritative.

Debate: make the models argue it out

Debate is the one we're most excited about, and the one nothing else does. Instead of each model answering once, the models you selected go back and forth.

Here's how a debate runs:

1. Opening answers. Each model answers the question independently — the same responses you'd see in any Deepest chat.
2. Critique and revise. Each model is shown the others' answers and asked to do three things: name the strongest point it missed, name the clearest weakness in another model's answer, and produce a revised answer. Crucially, they're instructed to hold their ground where they're right — to concede only to genuinely better arguments, not to be agreeable.
3. Converge or continue. After each round, Deepest checks whether the models have actually converged. If they have, it stops early. If they haven't, they go another round — up to three.
4. Review. Your chosen Deepest model steps in as a neutral referee — it wasn't one of the debaters — reads the final positions, and writes the unified answer. If the models never fully agreed, it says so honestly rather than faking consensus.

The result isn't just a blend of opinions. It's an answer that has survived cross-examination. In our own testing, a debate between two frontier models regularly produced a sharper framework than either model started with — the act of arguing forced them to find the distinctions a single pass glosses over.

Debate does more work — several rounds of model-to-model calls plus a final review — so it takes a little longer and costs more credits than a one-shot answer. It also settles the cost based on how many rounds the debate actually needed: when the models converge quickly, you pay less. Save it for the questions that genuinely deserve it — the strategic calls, the high-stakes trade-offs, the ones where you want the models to fight it out before you commit.

When to use which

A simple way to choose:

• Synthesis — "Give me the best answer." Fast, everyday, most questions.
• Compare — "Show me where they agree and disagree." For judgment calls where you want to see the split before you decide.
• Debate — "Make them argue it out and converge." For the hardest questions, where a battle-tested answer is worth the extra time and credits.

All three are available now in Deepest — pick a mode in the prompt bar whenever you have two or more models selected.

Frequently Asked Questions

Do I need to pick a mode every time?

No. Synthesis is the default, and you can set your preferred default in Settings. Compare and Debate are per-question choices you make in the prompt bar when a particular question calls for them.

Which models can debate each other?

Any two or more models you select. Debate works best with models that tend to reason differently — pairing temperamentally different models surfaces more genuine disagreement to work through, which is where Debate earns its keep. Your chosen Deepest model reviews the debate and writes the final answer, so it stays neutral rather than judging its own argument.

Why did "summary" become "synthesis"?

Because "summary" implied shortening, and that was never what the feature did. It merges the best reasoning from every model into one comprehensive answer — synthesis is the accurate word. The behavior is unchanged; only the name is clearer.

Is this what makes Deepest different from using one AI?

It's the core of it. Any single tool gives you one model's answer. Deepest gives you every top model at once — and then Synthesis, Compare, and Debate turn those answers into something more trustworthy than any one of them alone. That's the whole reason to use all of them instead of one.