open-browser

Unified browser automation MCP for AI agents — wraps Chrome DevTools, Playwright, and Lightpanda with a common interface, screenshot compression, and switchable backends.

Problem

chrome-devtools-mcp is great but has critical issues:

• take_screenshot returns raw PNG that can exceed 20MB, breaking MCP protocol
• No compression/resize before returning
• No backend flexibility (only Chrome)
• No smart routing (always spins up full Chrome even for simple fetches)

Solution

open-browser provides:

• Unified tool interface — same tools work across all backends
• Automatic screenshot compression — max 1200px, JPEG 70%, guaranteed <500KB
• Switchable backends — Chrome DevTools, Playwright, Lightpanda
• Smart auto-selection — light pages → Lightpanda, JS apps → Chrome, cross-browser → Playwright
• All the tools — navigate, click, fill, snapshot, screenshot, upload, evaluate, wait

Backends

| Backend | Speed | JS Support | Use case | |---------|-------|------------|----------| | Chrome DevTools | Medium | Full | Complex SPAs, auth flows, file uploads | | Playwright | Medium | Full | Cross-browser, PDF, reliable selectors | | Lightpanda | Fast (~10x) | Partial | Static pages, scraping, DOM inspection |

Installation

bun install -g @hasna/browser

Requirements

Note: The Bun.WebView engine requires Bun canary until WebView support lands in a stable release. Install with: bun upgrade --canary. Other engines (Playwright, CDP, Lightpanda) work with stable Bun.

Usage

# Default (Chrome DevTools backend)
browser serve

# Playwright backend
BROWSER_BACKEND=playwright browser serve

# Lightpanda backend
BROWSER_BACKEND=lightpanda browser serve

MCP Tools

All tools work identically across backends:

• navigate_page — Go to URL
• take_snapshot — Get accessibility tree (text, no size issues)
• take_screenshot — Compressed screenshot (max 1200px, JPEG 70%)
• click — Click element by UID
• fill — Fill input
• type_text — Type text
• press_key — Press keyboard key
• upload_file — Upload file to input
• evaluate_script — Execute JavaScript
• wait_for — Wait for element/condition
• new_page — Open new tab
• close_page — Close tab
• list_pages — List open tabs
• get_network_requests — Inspect network traffic

Status

🚧 In development. See tasks for progress.

License

Apache-2.0 — see LICENSE