# sidekar

> The utility layer for coding agents. One binary and one skill file give Claude Code, Codex, Copilot, Cursor, Gemini CLI, Grok, OpenCode, and Pi a real browser, macOS desktop control, an inter-agent bus, encrypted secrets, and durable memory. MIT licensed, runs locally, no MCP server.

## What is sidekar?

sidekar gives agents browser and desktop control, a local message bus, background jobs, encrypted secrets, optional remote relay, and local MITM debugging. It runs on your machine and does not replace the agent's control loop.

## Getting started

1. **Install:** `curl -fsSL https://sidekar.dev/install | sh` (installs the binary and runs `sidekar install` for agent skills).
2. **Launch an agent:** `sidekar <agent> [args…]` (e.g. `sidekar claude`, `sidekar codex`).
3. **Or run Sidekar directly:** `sidekar repl -c <credential> -m <model>`.
4. **Device login (optional):** `sidekar device login` for relay, web terminal, and encrypted secrets.
5. **Chrome extension (optional):** load from `extension/`, sign in from the popup, then `sidekar ext ...`.

## Components

**Runtime:** PTY wrapper (`sidekar claude`) or REPL (`sidekar repl`). Skill install via `sidekar install`.

**Communication:** local agent bus (SQLite): `bus who`, `bus send`, `bus done`. Works without login.

**Relay:** remote PTY bridge via `relay.sidekar.dev`. Requires device login. Web terminal and session list at sidekar.dev.

**Proxy (MITM):** local capture of agent-to-LLM HTTPS traffic into `proxy_log`. Flags: `--proxy`, REPL `/proxy`. CLI: `sidekar proxy log|show|clear`. Seven-day retention.

**Browser:** CDP automation (launch, read, click, screenshot, search, read-urls). Optional Chrome extension for everyday profiles (`sidekar ext`).

**Desktop:** macOS Accessibility API for native apps and windows.

**Background:** tab monitors (`monitor`), cron jobs, recurring loops (`loop`).

**Tools:** memory (explicit writes), tasks, automatic REPL journals, repo pack/tree, output compaction (`compact`).

**Secrets:** encrypted KV and TOTP. Device login unlocks encryption.

## Supported agents

`sidekar install` writes the skill file for Claude Code, Codex, Gemini CLI, Grok, OpenCode, and Pi. `sidekar <agent>` PTY-wrapping additionally covers Copilot and Cursor. Any other agent can call the `sidekar` CLI directly.

## Pricing

- Personal: Free (all features, no limits)
- Professional: $9/month (honor system, for work that pays)

## Links

- Website: https://sidekar.dev
- Docs: https://sidekar.dev/docs
- Install: https://sidekar.dev/install
- Full reference: https://sidekar.dev/llms-full.txt