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Preview of CLAUDEZILLA

CLAUDEZILLA by Boot Industries

Firefox automation for AI Agents (Claude Code, Pi, Mercury, omp, Hermes, MCP). Full browser control from the CLI for devs and headless agents: click, type, read pages by element refs, and take screenshots.

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Claudezilla.comClaudezilla dances in the bottom left corner of any Firefox tab that is being controlled by ClaudeClaudezilla tool calls within Claude CodeClaudezilla Firefox Extension v0.6.9Claudezilla FeaturesClaudezilla is open source on GithubClaudezilla dev depends on your support :)
About this extension
Claudezilla brings native Firefox browser automation to AI coding harnesses: Claude Code, Pi Agent, Mercury Agent, omp, Hermes Agent, and other MCP clients.

Control Firefox directly from your terminal: navigate pages, click elements, fill forms, capture screenshots, and analyze page content. A Google-free, telemetry-free alternative to Chrome-based browser automation.

FEATURES:
- Multi-harness support: automated registration for Claude Code and omp; the installer prints ready-to-paste configuration for Hermes, Pi and Mercury
- Full tool catalog by default, with tool titles and read-only/destructive annotations so harnesses can prompt sensibly. Lazy on-demand loading (--tools lazy) is available for token savings
- Stable element refs: accessibility snapshots return a compact text tree with [ref] handles you pass to click, type, scroll and press-key. A ref from an earlier page is reported as stale rather than acting on the wrong element
- firefox_find: locate elements by visible text or accessible name, with landmark context, instead of reading a whole page
- Page navigation and DOM interaction (click, type, scroll, press keys)
- Visible-text reading with paging: long pages are read in 20,000-character chunks
- Attach to existing user tabs: drive open browser tabs in place with explicit agent-initiated attach
- Never disturbs your browsing: agent tabs in a window you already have open are created inactive, so your selected tab is never taken over, and screenshots capture the agent's tab instead of the page you are looking at
- Vision-sized screenshots: the long edge is capped (1568 px by default) so images are not downscaled again by the model, with region zoom and dynamic readiness detection. Optional save to a private temporary file for harnesses that cannot display inline images
- Annotated screenshots with numbered badges that map to element refs
- Structured page analysis via JSON with configurable limits and explicit truncation metadata (faster and cheaper than screenshots)
- Page state diffing to detect changes between interactions
- Cookie and consent banner auto-dismissal (GDPR overlays, CMP platforms)
- Domain allowlists for agent sandboxing
- Flexible element waiting (CSS selector, text content, or URL pattern)
- No hangs on unpainted tabs: animation-frame waits are bounded, so commands settle in a background tab, a minimised window or another workspace
- Network request and console log monitoring
- Multi-agent and multi-harness safety: tab ownership tracking (including navigation), screenshot mutex, and slot reservations
- Focus loops that keep running across agent sessions (state lives in the host process)
- Orphaned tab cleanup with configurable timeout (CLAUDEZILLA_AGENT_TIMEOUT_MS): set it to 0 to switch cleanup off entirely
- Start Firefox on demand: CLAUDEZILLA_AUTOSTART_CMD launches the browser when the host is not reachable (run as an argv vector, never through a shell). Listing tools and shutting down never start the browser
- Two browser profiles side by side: CLAUDEZILLA_IPC_DIR (POSIX only) relocates the IPC socket, auth token and debug log
- Per-operation timeouts (5s-300s, default 150s)
- A portable "claudezilla-browser" Agent Skill that teaches harnesses the efficient workflow (read refs first, screenshot only when needed)

REQUIREMENTS:
- Supported AI harness: Claude Code, Hermes Agent, Pi Agent, omp, Mercury, or any standard MCP client
- Native messaging host and MCP server (one-command installer; --target for Claude Code, omp, Hermes, Pi and Mercury on macOS and Linux; the Windows installer configures Claude Code). Keep the extension and the MCP server on the same version
- Firefox 140+
- macOS, Linux, or Windows 10/11

PRIVACY & SECURITY:
- All communication is local via Unix socket / Windows pipe (no network exposure)
- Zero telemetry: no data collected or transmitted to external servers
- Page content accessed only on explicit tool invocation
- Console capture and JavaScript evaluation are strictly opt-in (off by default in popup settings)
- The installers' MCP allow-list does not pre-approve firefox_evaluate, so the tool is not silently permitted by the harness either
- Screenshot save paths are restricted to the temp and working directories and written owner-only
- Request bodies are never captured, and typed text is not logged
- Per-agent tab ownership prevents cross-session and cross-harness interference
- Community supported
- Open source (MIT license)

Setup & docs: claudezilla.com
Developer comments
Requires native messaging host for operation. Designed for Claude Code CLI (https://claude.com/claude-code) - browser automation for AI-assisted development.

Installation docs: https://claudezilla.com/extension.html

Permission justifications:
• nativeMessaging: Core functionality
• tabs/activeTab: Tab management
• <all_urls>: Content script for DOM interaction
• webRequest/webRequestBlocking: Page readiness detection
• storage: User preferences

No external data collection. All communication local via Unix socket.
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Permissions and data

Required permissions:

  • Exchange messages with programs other than Firefox
  • Access browser tabs
  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
0.7.7
Size
333.27 KB
Last updated
7 days ago (Nov 5, 2026)
Related Categories
  • Web Development
  • Search Tools
  • Tabs
License
MIT License
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Version History
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Tags
  • chat
  • privacy
  • user scripts
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