agent-browser

agent-browser

Browser automation CLI designed for AI agents. Compact text output minimizes context usage. Fast Rust CLI with Node.js fallback.

npm install -g agent-browser      # all platforms (fastest, native Rust CLI)
brew install agent-browser        # macOS

# or try without installing
npx agent-browser open example.com

Features

  • Agent-first - Compact text output uses fewer tokens than JSON, designed for AI context efficiency
  • Ref-based - Snapshot returns accessibility tree with refs for deterministic element selection
  • Fast - Native Rust CLI for instant command parsing
  • Complete - 50+ commands for navigation, forms, screenshots, network, storage
  • Sessions - Multiple isolated browser instances with separate auth
  • Cross-platform - macOS, Linux, Windows with native binaries

Works with

Claude Code, Cursor, GitHub Copilot, OpenAI Codex, Google Gemini, opencode, and any agent that can run shell commands.

Example

# Navigate and get snapshot
agent-browser open example.com
agent-browser snapshot -i

# Output:
# - heading "Example Domain" [ref=e1]
# - link "More information..." [ref=e2]

# Interact using refs
agent-browser click @e2
agent-browser screenshot page.png
agent-browser close

Why refs?

The snapshot command returns a compact accessibility tree where each element has a unique ref like @e1, @e2. This provides:

  • Context-efficient - Text output uses ~200-400 tokens vs ~3000-5000 for full DOM
  • Deterministic - Ref points to exact element from snapshot
  • Fast - No DOM re-query needed
  • AI-friendly - LLMs parse text output naturally

Architecture

Client-daemon architecture for optimal performance:

  1. Rust CLI - Parses commands, communicates with daemon
  2. Node.js Daemon - Manages Playwright browser instance

Daemon starts automatically and persists between commands.

Platforms

Native Rust binaries for macOS (ARM64, x64), Linux (ARM64, x64), and Windows (x64).