Ghostfox

The agent-native stealth browser you can own.

Self-hosted · Open source · MCP-first · Engine-level anti-detect

Watch the full demo · Docs site

AI agents get blocked. Headless Chrome triggers Cloudflare 403s on ~20% of the web, and hosted "stealth browsers" route your agent's cookies, identities and sessions through someone else's cloud.

Ghostfox is the alternative: a complete browser stack you run yourself — a fingerprint-coherent stealth engine plus a Rust MCP runtime, in one repo.

Firefox (MPL-2.0)
  └─ Camoufox (anti-detect patches, by daijro)
       └─ Ghostfox engine          engine/   — spoofing at the C++ level
            └─ Ghostfox runtime     runtime/  — Rust: sessions, identities, MCP

Eyes for agents — page_a11y. One call returns every visible interactive element with a stable ref, semantic role, accessible name, live value — piercing shadow DOM and same-origin iframes, so web-component UIs (Reddit, modern frameworks) are fully visible. The snapshot also reports login_state (logged-in / logged-out / unknown), page URL and title — agents check session health before acting, not after failing.

Agents act by ref: page_click_ref e38, page_type_ref e21 "text" — no CSS selectors needed. Rich editors (Lexical, Draft, ProseMirror) are handled via editor-native input paths with fire-then-verify receipts. page_wait_for replaces manual sleeps. page_read_ref gives full untruncated values. page_upload_file bypasses native file pickers.

Android personas too — session_create {"platform": "android"} gives portrait screens, Adreno/Mali GPUs, Android font stacks and Firefox-on-Android UAs, all audited like desktop identities (500/500 coherent, see runtime/docs).

One identity, no contradictions. Identities are generated from coherent device presets (platform, screen, GPU, fonts that actually ship together), injected at the engine level, and audited before use — a spoofed browser's worst enemy is itself saying "4 cores on a MacBook".

Quickstart

Requires: Rust toolchain (Linux, macOS, or Windows). Prebuilt engine binaries: see Releases.

# 1) Get the engine (prebuilt) and unpack it somewhere, e.g. /opt
unzip ghostfox-<ver>-lin.x86_64.zip -d /opt/ghostfox

# 2) Build the runtime
git clone https://github.com/autokeren/ghostfox.git
cd ghostfox/runtime
cargo build --release

# 3) Wire it into any MCP client (Claude Code, Cursor, ...)

{
  "mcpServers": {
    "ghostcloak": {
      "command": "/path/to/ghostfox/runtime/target/release/ghostcloak-mcp",
      "env": { "GHOSTFOX_HOME": "/opt/ghostfox" }
    }
  }
}

Then the agent can: session_create → page_open → page_a11y → act by ref.

Full tool surface (19 tools):

Every mutation returns a receipt — page_fill reports landed_chars, while type_ref fire-then-verifies async editors, so a silent page swap can't eat an edit unnoticed. Sessions can also run headful ({"headful": true}) when humans want to watch the agent work.

Every run records evidence. Each session writes an append-only event log (events.jsonl), full page snapshots and the identity it used under ~/.ghostfox/recordings/ — fetch it any time with session_evidence.

Or install in one command (Linux x86_64):

curl -fsSL https://raw.githubusercontent.com/autokeren/ghostfox/main/install.sh | bash

From source end-to-end (build the engine yourself): see engine/README.md — make dir && make build.

Repository layout

runtime/   Rust: ghostcloak-{core,fingerprint,mcp,eval}     (MIT OR Apache-2.0)
engine/    Browser fork: patches, branding, build system    (MPL-2.0)
AGENTS.md  The agent playbook — how AI agents drive Ghostfox like a human

Two directories, two licenses, one product. The runtime speaks Juggler natively — no Node, no Python at runtime.

Using Ghostfox with an AI agent (opencode, Codex, Cursor, Claude Code, ...)? Read AGENTS.md first — it's the distilled playbook from real agent runs: the READ → REASON → DECIDE → ACT loop, self-health (rate limits, drafts, notifications), rich-editor typing, and every known wall with its proven solution.

Why own the engine?

• Anti-detect that survives inspection. Spoofing happens inside the engine (navigator, screen, WebGL, fonts, WebRTC, timezone, audio) — not in injected JS that detectors can read.
• No cloud dependency. Your agent's identities and cookies never touch a third-party host.
• Upstream insurance. engine/ tracks daijro/camoufox as upstream; Ghostfox applies its own branding and can rebase whenever it wants — including if upstream patches go closed-source.

Status

Pre-alpha. Verified: identity coherence (500/500), full MCP round-trip E2E (create → open → fill → submit), multi-page sessions. Known limits are tracked in the changelogs under runtime/ and engine/.

Do not use against targets you don't have permission to test. This is a testing / research tool.

Credits

Ghostfox stands on the shoulders of giants — Camoufox (daijro) for the anti-detect patch stack, Mozilla Firefox for the engine, LibreWolf for the patch tooling lineage, and Playwright for the Juggler protocol.

License

• engine/ — MPL-2.0 (inherited from Firefox / Camoufox). See engine/LICENSE.
• runtime/ — MIT OR Apache-2.0. See runtime/LICENSE-MIT.