Rust CLI that connects to an existing Chrome browser via the DevTools Protocol. Auto-connects by default — no manual WebSocket URL needed.

brew tap aeroxy/chrome-devtools-cli
brew install chrome-devtools

cargo install chrome-devtools-cli

The installed binary is named chrome-devtools.

cargo build --release
# Binary: ./target/release/chrome-devtools

Inspired by chrome-devtools-mcp — the official MCP server for Chrome DevTools. It works well, but MCP-based browser tools consume a lot of token context: every interaction sends and receives large protocol payloads through the MCP layer.

99% of the time the browser being controlled is the user's own Chrome with their own credentials, so there is no need for a full headless browser stack like Puppeteer or Playwright, and no need for the MCP overhead.

This is a lightweight Rust binary that talks directly to Chrome's DevTools Protocol. One command in, one result out. No separate browser process, no credential handoff, no heavyweight runtime. The agent skill for this tool is a single SKILL.md file — the entire context overhead is this documentation.

chrome-devtools navigate https://example.com
        │
        ├─ Try daemon (Unix socket /tmp/chrome-devtools-daemon.sock)
        │   └─ If running → send command → get result
        │
        ├─ If no daemon → spawn one (background process)
        │   └─ Daemon connects to Chrome WebSocket (one-time approval)
        │   └─ Listens on Unix socket, 5-min idle timeout
        │
        └─ Fallback → direct WebSocket connection (no daemon)

The daemon keeps a persistent WebSocket connection to Chrome, so the browser only prompts for DevTools access once. Subsequent commands reuse the connection.

Chrome must have remote debugging enabled:

1. Open Chrome
2. Go to chrome://inspect/#remote-debugging
3. Enable the remote debugging server

By default, the CLI reads DevToolsActivePort from Chrome's user data directory:

Override with --user-data-dir, --channel (beta/canary/dev), or --ws-endpoint.

Every page-level command outputs a friendly target name like [target:red-snake]. This is a deterministic word-pair derived from Chrome's internal target ID — same page always gets the same name.

# Navigate — note the target name
chrome-devtools navigate https://example.com
# Navigated to https://example.com
# [target:red-snake]

# Pin subsequent commands to the same page
chrome-devtools --target red-snake screenshot --output /tmp/page.png
chrome-devtools --target red-snake evaluate "document.title"

Without --target, commands default to page index 0, which may vary as Chrome reorders tabs. Always capture and reuse the target name.

list-pages shows all pages with their friendly names:

[0] (green-dog) My App — https://localhost:3000
[1] (red-snake) Example Domain — https://example.com
[2] (bold-stag) GitHub — https://github.com

You can also use --page <index> for quick one-offs, or pass the raw hex target ID.

• Socket: /tmp/chrome-devtools-daemon.sock
• PID file: /tmp/chrome-devtools-daemon.pid
• Idle timeout: 5 minutes (auto-exits, cleans up socket)
• Protocol: Length-prefixed JSON over Unix socket
• Spawned by: First CLI invocation (transparent to user)
• Kill manually: pkill -f __daemon__ or delete the socket

src/
├── main.rs         # CLI (clap) + daemon-first dispatch
├── cdp.rs          # Raw CDP over WebSocket (JSON-RPC)
├── browser.rs      # Auto-connect (DevToolsActivePort)
├── daemon.rs       # Background daemon (persistent connection)
├── client.rs       # Talks to daemon via Unix socket
├── protocol.rs     # IPC message types
├── friendly.rs     # Target ID → word-pair names
└── commands/
    ├── navigate.rs
    ├── pages.rs    # list/new/close/select/resize/wait-for
    ├── screenshot.rs
    ├── evaluate.rs
    ├── input.rs    # click/fill/type/press/hover
    └── snapshot.rs

# 1. Navigate — capture the [target:name]
chrome-devtools navigate https://example.com
# [target:red-snake]

# 2. Understand the page
chrome-devtools --target red-snake snapshot
chrome-devtools --target red-snake screenshot --output /tmp/page.png

# 3. Interact
chrome-devtools --target red-snake fill "#email" "user@example.com"
chrome-devtools --target red-snake click "#submit"

# 4. Extract data
chrome-devtools --target red-snake evaluate "document.title"

Always pass --target from step 2 onward to stay on the same page.

skill/chrome-devtools/SKILL.md is a Claude Code skill that teaches the agent how to use this binary. Drop it into any Claude Code plugin's skills/ directory and set chrome-devtools to the binary path. The skill covers the full workflow, all commands, and the --target pinning pattern — everything needed to reliably automate Chrome without large context overhead.

MIT