Sidecar for agent CLIs.

Sidekar sits next to Claude Code, Codex, Cursor, Gemini CLI, and the rest. One binary, one skill file. Not an orchestrator or agent OS. Wrap your usual agent, or run Sidekar on its own in the REPL.

Install the CLI Read the docs
No MCP Runs locally by default Relay needs device login
Overview

What Sidekar handles.

Each card links to a docs section with commands and examples. Almost everything runs on your machine. Relay is the main exception.

Run and connect

Runtime

Wrap an existing agent CLI, or run Sidekar as the agent in the REPL.

sidekar claude, sidekar repl

Communication

Local bus for handoffs between terminals on the same machine.

sidekar bus who, send, done

Relay

Web terminal and session list through relay.sidekar.dev.

sidekar device login, --relay

Proxy (MITM)

Capture agent-to-LLM API traffic locally when you need to debug.

--proxy, sidekar proxy log
Automate

Browser

CDP automation, plus an optional Chrome extension for everyday profiles.

sidekar read, click, ext

Desktop

macOS native UI: windows, clicks, keys, screenshots outside Chrome.

sidekar desktop apps, click
Persist and schedule

Background

Cron jobs, recurring loops, and tab monitors that outlive one prompt.

sidekar cron, loop, monitor

Tools

Memory, tasks, journals, repo context, and output compaction.

sidekar memory, tasks, compact

Secrets

Encrypted KV and TOTP. Device login unlocks encryption.

sidekar kv, totp
Install

Get running.

Four steps. Only the first is required.

Step 1
Install Sidekar

Run curl -fsSL https://sidekar.dev/install | sh. This also runs sidekar install for agent skills.

Step 2
Launch your agent

Wrap your usual CLI with sidekar <agent> [args], or run sidekar repl -c <credential> -m <model>.

Step 3
Device login (optional)

sidekar device login unlocks relay, the web terminal, encrypted secrets, and session management.

Step 4
Chrome extension (optional)

For everyday Chrome profiles and history. See the extension page.

Examples

Where it helps.

Sidekar is most useful when work jumps between terminals, browsers, and native apps.

Ship and verify

One agent edits code, another checks the deployed page in Chrome, a third signs off. The bus carries results so you are not copy-pasting between windows.

  • sidekar codex builds the change
  • sidekar read or sidekar ext read checks the live page
  • sidekar bus send hands off to QA

Finish login flows

Pull credentials from encrypted storage, generate TOTP codes, and drive the browser through the rest of the flow.

  • Encrypted KV for secrets
  • TOTP on demand
  • Browser and desktop commands for the UI steps

Pick up where you left off

Memory, tasks, repo packs, and compact command output stay on disk between sessions.

  • sidekar memory context loads project memory
  • sidekar tasks list --ready shows unblocked work
  • sidekar repo pack ships repo context to the model

Background checks

Watch a dashboard tab, schedule a cron prompt, or loop a recurring check. Results can land back on the bus.

  • sidekar monitor start all for tab changes
  • sidekar cron create for scheduled runs
  • sidekar loop for recurring prompts

Debug and remote check-in

Turn on MITM capture when API traffic looks wrong, or attach through relay when a long session is running elsewhere.

  • sidekar claude --proxy logs API calls locally
  • sidekar claude --relay opens a web terminal
  • Active sessions at sidekar.dev/sessions
Privacy

Local first.

Browser automation, the bus, secrets, TOTP, and proxy traces stay on your machine. Sign in at sidekar.dev only when you want relay, the dashboard, or the web terminal.

What stays local

Browser and desktop automation, bus delivery, encrypted secret storage, and TOTP generation all run locally. The extension talks to a bridge on 127.0.0.1. It does not browse on its own; it waits for your Sidekar process to tell it what to do.

Relay sends session metadata (name, hostname, working directory, agent type) so the dashboard can list active sessions. See the privacy policy for the full breakdown.

Install sidekar Open docs