> ## Documentation Index
> Fetch the complete documentation index at: https://docs.trynito.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Model Fusion

> Two or three models on one prompt plus a synthesis, through the API, Browser App, and Plugin.

Model Fusion sends one prompt to two or three models at once, then a judge model reads every answer and writes one merged reply. You get the synthesis and each participant's output.

## Where

* **API**, with [`POST /api/v1/chat/fusion`](/api/api-reference/chat-and-text/chat-fusion) and an API key.

* **Browser App**, from the composer. See [Fusion](/web-app/fusion).

* **Plugin**, with `/nito:fusion` or `$nito:fusion`. See [Fusion in the plugin](/plugin/commands/fusion).

* **MCP**, through the `nito.chat_fusion` tool on the hosted endpoint.

Fusion needs a paid plan. See [Plans](/plans).

## How It Works

1. **Fan-out.** Anonymous and Private models run concurrently; all-Confidential sets run one at a time inside attested routes.
2. **Synthesis.** A judge model merges the answers. For all-Confidential sets, one Confidential participant is the judge, so the synthesis stays attested.

The result arrives once every participant and the synthesis finish. A failed participant is reported in its own entry.

## Privacy Rules

* Anonymous and Private models can mix.
* Confidential models run only with other Confidential models, judge included.
* Encrypted Fusion runs in the Browser App, with the synthesis as an explicit step.

## From Your Own Code

Call [`POST /api/v1/chat/fusion`](/api/api-reference/chat-and-text/chat-fusion) with `models` and `messages`. The response includes each participant and the synthesis. Each participant and the synthesis meter separately. A paid plan with Fusion access is required; prepaid balance alone does not unlock it.

## Related

<CardGroup cols={3}>
  <Card title="Fusion in the Browser App" icon="layer-group" href="/web-app/fusion">
    Pick and compare.
  </Card>

  <Card title="Fusion in the Plugin" icon="terminal" href="/plugin/commands/fusion">
    Claude Code and Codex.
  </Card>

  <Card title="Fusion API" icon="book" href="/api/api-reference/chat-and-text/chat-fusion">
    HTTP examples and results.
  </Card>
</CardGroup>


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