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

# Reasoning Engines

> Side-by-side comparison of MIRA's two engines — Native Agent Engine and RLM — with guidance on when to use each.

MIRA ships with two reasoning engines. The active engine is shown in the status bar at the bottom of the window. Switch between them in **Settings → Engine** (⌘,).

## Engine comparison

<Snippet file="rlm-nae-comparison-table.mdx" />

## Engine status

<Snippet file="engine-status-badge.mdx" />

## Switching engines

Switching engines **resets the active session** — context, history, and document context from one engine are not carried over to the other. This is intentional: the two engines maintain fundamentally different internal state.

To switch:

1. Open **Settings** (⌘,)
2. Go to the **Engine** tab
3. Click the engine you want to activate
4. A confirmation dialog appears if there is an active session
5. The status bar updates immediately

Your engine choice is persisted across restarts.

## Configuration

Each engine has its own configuration panel in **Settings → Engine**:

* [NAE Settings Reference](/configuration/nae-settings) — provider, model, context budget, multi-agent mode, MCP timeout
* [RLM Settings Reference](/configuration/rlm-settings) — provider, model, temperature, iteration limits, chunking strategy

## Deep dives

<CardGroup cols={2}>
  <Card title="Native Agent Engine" icon="cpu" href="/core-concepts/native-agent-engine">
    How NAE manages token budgets, compacts context, spawns sub-agents, and maintains episodic
    memory
  </Card>

  <Card title="RLM Engine" icon="terminal" href="/core-concepts/rlm-engine">
    How RLM writes code, executes it, interprets output, and iterates to a verified answer
  </Card>
</CardGroup>