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

# Plugin system

> Understand plugin delivery, profile scope, desktop integration, and recovery.

Harness plugins can extend the host runtime, contribute tools, and add UI integrations.
The desktop app adds lifecycle management and a controlled bridge to native features.

## Responsibilities

| Component           | Responsibility                                                      |
| ------------------- | ------------------------------------------------------------------- |
| Harness host plugin | Registers tools, routes, system context, and lifecycle hooks        |
| Client plugin       | Adds panels or UI behavior to the Harness web application           |
| Tauri bridge plugin | Exposes approved desktop commands and events to the embedded client |
| Desktop manager     | Installs, upgrades, removes, repairs, and reports plugin state      |
| Profile             | Owns its plugin declarations and configuration                      |

## Internal plugin lifecycle

Before Harness starts, the desktop workflow ensures required first-party integrations
exist in the active profile. Missing or inconsistent declarations are restored from the
copies bundled with the application. This makes native settings and panel features
available even after an interrupted update.

Optional preset and community plugins follow normal install, upgrade, and uninstall
flows. The Windows Minimal repair plugin is fetched from GitHub when selected; it is not
bundled source.

## Communication path

1. The embedded Harness client invokes an integration exposed by its client plugin.
2. The plugin sends a structured request through the desktop bridge.
3. Tauri command handlers validate the operation and call the responsible Rust service.
4. Results or lifecycle events return to the client and update its panel state.

<Warning>
  Plugin installation is code installation. Profile scoping prevents configuration
  collisions, not malicious filesystem, process, credential, or network access. Review
  third-party source and pin trusted versions where possible.
</Warning>

For user-facing operations, see [Plugins](../guides/plugins).