# Packages & MCP Servers

Community packages and external servers installed by default.

> 📋 **Architecture Decision Records:** Each package has a lightweight ADR in
> [`docs/adr/`](adr/) documenting the rationale, alternatives, and research evidence.
> See [adr-0012 through adr-0018](adr/README.md).

## Core Packages

These add functional capabilities to the agent:

| Package                                                                                | What it does                                                                  |
| -------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------- |
| [`pi-subagents`](https://www.npmjs.com/package/pi-subagents)                           | Chain, parallel, async subagent orchestration (`/run`, `/chain`, `/parallel`) |
| [`pi-intercom`](https://www.npmjs.com/package/pi-intercom)                             | Live coordination between parent and child agents (`contact_supervisor`)      |
| [`pi-web-access`](https://www.npmjs.com/package/pi-web-access)                         | Web search, content fetching, GitHub repo cloning                             |
| [`pi-lens`](https://www.npmjs.com/package/pi-lens)                                     | Real-time LSP diagnostics, type-checking, and linter feedback                 |
| [`pi-mcp-adapter`](https://www.npmjs.com/package/pi-mcp-adapter)                       | MCP (Model Context Protocol) server integration                               |
| [`pi-model-aware-compaction`](https://www.npmjs.com/package/pi-model-aware-compaction) | Auto-compaction tuned to each model's context window                          |

## UI & Polish Packages

Cosmetic and quality-of-life improvements:

| Package                                                                    | What it does                                                   |
| -------------------------------------------------------------------------- | -------------------------------------------------------------- |
| [`pi-powerline-footer`](https://www.npmjs.com/package/pi-powerline-footer) | Status bar with git branch, thinking indicator, and sparklines |

## MCP Servers

| Server                                       | What it does                                                        |
| -------------------------------------------- | ------------------------------------------------------------------- |
| [Playwright MCP](https://playwright.dev/mcp) | Browser automation (Chromium, Firefox, WebKit) with profile support |

Installed automatically. Config in `mcp.json` + `playwright-mcp.json`. See [browser-mcp.md](browser-mcp.md) for browser setup options.

## Updating Packages

```bash
pi update                  # Update pi binary + all packages
pi update --self           # Update pi binary only
pi update --extensions     # Update packages only
```

Pinned versions are skipped.
