gomoufox

gomoufox is a Go driver for Camoufox.

It gives Go programs, shell scripts, and MCP agents a typed way to launch and control the pinned Camoufox browser stack without writing Python glue.

Use it only on sites you own, test, or have permission to automate.

At a glance

Need	Use
Go browser automation	github.com/ehmo/gomoufox
Shell automation	gomoufox get, gomoufox screenshot, gomoufox fetch
Agent browser tools	gomoufox mcp
Agent instructions	gomoufox skills list, show, export, install
Release evidence	docs/BENCHMARKS.md

flowchart LR
  GoApp["Go app"] --> GoAPI["Go API"]
  Shell["Shell script"] --> CLI["gomoufox CLI"]
  Agent["Agent"] --> Skills["SKILL.md"]
  Skills --> MCP["gomoufox mcp"]
  GoAPI --> Sidecar["gomoufox sidecar"]
  CLI --> Sidecar
  MCP --> Sidecar
  Sidecar --> Camoufox["Pinned Camoufox"]
  Camoufox --> Web["Permitted sites"]

  classDef api fill:#00ADD8,color:#ffffff,stroke:#00758f;
  classDef agent fill:#7c3aed,color:#ffffff,stroke:#5b21b6;
  classDef browser fill:#f97316,color:#ffffff,stroke:#c2410c;
  classDef web fill:#16a34a,color:#ffffff,stroke:#15803d;
  class GoAPI,CLI api;
  class Agent,Skills,MCP agent;
  class Sidecar,Camoufox browser;
  class Web web;

Loading

Install

Library:

go get github.com/ehmo/gomoufox

CLI:

go install github.com/ehmo/gomoufox/cmd/gomoufox@latest
gomoufox install
gomoufox doctor

Homebrew:

brew tap ehmo/gomoufox https://github.com/ehmo/gomoufox
if brew commands | grep -qx trust; then
  brew trust --formula ehmo/gomoufox/gomoufox
fi
brew install gomoufox
gomoufox install
gomoufox doctor

Install through the tap. Current Homebrew rejects standalone formula files from outside a tap, so the release gomoufox.rb asset is for audit and tap metadata, not the primary install path.

Run brew trust only when your Homebrew version supports it. Newer Homebrew builds may omit that command.

The Homebrew formula installs only on platforms where the pinned Camoufox browser has a supported upstream binary: macOS Apple Silicon and Linux amd64. The release still publishes all Go archives for library and CLI users.

gomoufox install creates a managed Python environment, installs hash-locked Python packages, and fetches the pinned browser binary. Go callers still use the Go API and CLI. The Python environment is runtime plumbing for Camoufox.

Python remains required because Camoufox owns launch-option generation, BrowserForge fingerprint generation, geoip handling, and browser payload validation. gomoufox keeps that boundary explicit: launcher arguments are passed over stdin, the launcher file does not persist proxy credentials, and browser processes inherit the operating-system environment with secret-like and agent-control variables removed. Values you pass with WithExtraEnv are added explicitly. Generated launch payloads are not cached because they include fresh fingerprint state.

Use GOMOUFOX_CAMOUFOX_PATH when you already have a compatible Camoufox browser directory and want gomoufox to use it instead of the managed one. gomoufox verifies the pinned browser manifest for that path by default. For trusted local Camoufox builds that do not match the release manifest, set GOMOUFOX_TRUST_UNVERIFIED_CAMOUFOX_PATH=1; gomoufox doctor reports that as a warning.

Python packages are installed from embedded lock files with --require-hashes and --only-binary=:all:. A missing wheel or hash mismatch fails the install instead of falling back to an unpinned source build. Regenerate the locks only when changing the version matrix:

python3 scripts/update-python-locks.py

Go library

package main

import (
	"context"
	"fmt"

	gomoufox "github.com/ehmo/gomoufox"
)

func main() {
	ctx := context.Background()

	browser, err := gomoufox.New(ctx)
	if err != nil {
		panic(err)
	}
	defer browser.Close()

	page, err := browser.NewPage(ctx)
	if err != nil {
		panic(err)
	}

	if _, err := page.Goto(ctx, "https://example.com"); err != nil {
		panic(err)
	}

	text, err := page.Content(ctx)
	if err != nil {
		panic(err)
	}
	fmt.Println(text)
}

Use the library when your program owns the browser lifecycle. Use the CLI when a shell script needs a page snapshot, screenshot, or browser-context fetch. Use MCP when an agent needs browser tools over stdio or HTTP.

CLI

gomoufox get https://example.com --markdown
gomoufox screenshot https://example.com --out page.png --full-page
gomoufox fetch https://api.example.com/me --navigate-first https://example.com

Fetch responses are read through a bounded browser stream. gomoufox fetch defaults to 512 KiB, reports truncation in JSON output, and cancels the reader when the cap is reached.

Agent-friendly discovery:

gomoufox help
gomoufox help --json --fields commands
gomoufox help skills --json
gomoufox help mcp --json
gomoufox skills list --json
gomoufox skills show core
gomoufox mcp --help

Automation tips:

• Use --json for machine-readable output and keep status logs on stderr.
• Use --timeout <dur> for bounded shell jobs.
• Use --profile <dir> when a workflow needs persistent browser state.
• Keep the default URL policy for normal work. Use --allow-private-ips only when you need local or private network targets.

Skills

gomoufox ships versioned agent skills in the binary and as checked SKILL.md files. Skills give agents a compact operating guide for the Go API, CLI, and MCP tools. They do not install npm packages, run npx, or call the network.

Skill	Path	Use it when
core	skills/gomoufox/SKILL.md	An agent needs the Go library or CLI workflow.
mcp	skills/gomoufox-mcp/SKILL.md	An agent needs MCP setup, tool choice, and browser safety rules.

Inspect the embedded skills:

gomoufox skills list --json
gomoufox skills show core
gomoufox skills show mcp

Export installable copies:

gomoufox skills export --out ./skills
gomoufox skills export --out ./skills --force

Install them for Codex:

gomoufox skills install --target codex --dry-run --json
gomoufox skills install --target codex

By default, the Codex target writes to $CODEX_HOME/skills or ~/.codex/skills. Use --dir <path> to choose another skill directory. The installer writes:

• gomoufox/SKILL.md
• gomoufox/agents/openai.yaml
• gomoufox-mcp/SKILL.md
• gomoufox-mcp/agents/openai.yaml

list and show read from the embedded skill bodies, so agents can discover the right instructions even when no skill directory exists yet. export and install write the same checked bodies that ship in the repo. Existing files are left alone unless you pass --force.

MCP

Run browser tools over stdio:

gomoufox mcp

Claude Code example:

claude mcp add gomoufox -- gomoufox mcp

HTTP transport requires a bearer token:

gomoufox mcp --transport http --auth-token "$TOKEN"

MCP defaults:

• Use gomoufox mcp --toolset core for a smaller agent tool surface. It keeps navigation, snapshots/content, common form actions, sessions, and skill tools. The default full toolset keeps diagnostics, eval, fetch, cookies, storage, upload, and other gated tools available.
• file://, private IP ranges, link-local addresses, and metadata hosts are blocked.
• JavaScript evaluation is disabled unless you start MCP with --enable-eval.
• Response sizes are capped.
• MCP-owned helper scripts use a startup-probed internal helper evaluation path and do not install a page-visible helper object.
• Browser-derived MCP responses include provenance.trust: "untrusted" so agents can separate website content from trusted instructions. This label helps agent policy. It is not a sandbox.
• Console, page-error, network, and performance diagnosis tools are bounded, redacted, and clearable where they keep event buffers. Network summaries do not include request or response bodies.
• Ref-based interaction tools cover click, type, key press, hover, scroll, select option, checkbox/radio state, dialog policy, and bounded form batches.
• browser_snapshot form values stay redacted unless you start MCP with --allow-snapshot-values and the tool call sets include_values: true.
• Browser-context fetches, cookie values, cookie mutation, session export, session import, session proxy use, and file upload stay disabled unless you enable their matching operator flags.
• browser_upload_file requires --allow-file-upload; paths must resolve under --session-dir, and responses do not echo file paths.
• browser_fetch requires --allow-browser-fetch plus at least one --allowed-origins or --allowed-hosts entry. It still uses gomoufox network policy, so private and metadata destinations stay blocked.

Benchmarks

gomoufox includes a repeatable benchmark that runs gomoufox and Python Camoufox against the same real-site target set and records outcomes, wall time, peak RSS, peak CPU, resource ratios, and estimated report-token footprint. The parity run uses generated personas and --unsafe-direct-network; local URL guardrails are tested by separate CLI and MCP tests.

Latest checked baseline: see docs/BENCHMARKS.md.

Runtime	Passed	Blocked	Failed	Wall ms	Peak RSS MiB	Peak CPU %	Report tokens
gomoufox	95	5	0	366,338	2,765.3	569.9	13,059
Python Camoufox	95	5	0	363,961	3,083.2	483.1	68,307

Latest extended validation: 100 targets, 45s timeout, commit wait, 3s settle, no screenshots, built gomoufox realpass binary, reused browser, compact Go report, 0s extra load-state wait, and 250,000-byte classification cap. Both runtimes passed 95, blocked 5, failed 0, with zero outcome mismatches. See docs/benchmarks/2026-06-08-release-gate.json.

Ratio	Go / Python
Wall time	1.007
Peak RSS	0.897
Peak CPU	1.180
Report tokens	0.191

Serial wall time varies because Firefox dominates the run. The checked wins are lower RSS and a smaller agent report. Go wall time was effectively parity but slightly slower in this serial run, and Go peak CPU stayed inside the 1.50 release budget. Treat a report-token ratio above 0.50 as a regression.

scripts/benchmark-realpass.py --mode smoke
scripts/benchmark-realpass.py --mode smoke --loops 2 --run-order alternate
scripts/benchmark-realpass.py --mode extended --list-targets
scripts/fingerprint-audit.py

Run the fingerprint audit when changing launch options, sidecar runtime code, Camoufox pins, Firefox prefs, WebGL handling, locale, timezone, screen, fonts, canvas, or node-direct. It serves one local page, captures Python Camoufox, gomoufox with the Python sidecar, and gomoufox with node-direct, then fails on unexplained gomoufox Python-vs-node-direct drift. Python Camoufox direct is kept as baseline context because its generated persona can legitimately differ on a single local run.

For a new checked baseline, run full mode with --update-doc docs/BENCHMARKS.md and commit the generated JSON under docs/benchmarks/.

Use --mode extended for the 100-target matrix before release candidates or major browser, sidecar, MCP, CLI, or resource-related changes. The catalog lives in scripts/realpass-targets.json; the runner also accepts --max-targets <n> for bounded investigations. Use --run-order alternate for timing work so Go and Python both take a turn running after warmed OS and network caches.

Release gates fail on Go-only blocked, failed, or missing targets; Go/Python outcome mismatches that reproduce on retry; missing required targets; peak RSS or CPU over budget; and Go wall time, target duration, RSS, CPU, or report-token ratios over the thresholds in docs/BENCHMARKS.md. In release mode, a new shared block, failure, or performance outlier gets one focused retry. The gate merges that focused retry back into the full report, then reruns the strict resource, timing, required-target, and token checks.

Python-removal work has its own promotion check. A node-direct run must use the extended target matrix, match Python outcomes with zero runtime failures, and beat Python on wall time, target duration, RSS, CPU, and report-token ratios before it can replace the Python sidecar:

scripts/benchmark-realpass.py --mode extended --go-sidecar-runtime node-direct
python3 scripts/check-python-removal-readiness.py --artifact docs/benchmarks/<run>.json

Until that check reports candidate, node-direct stays experimental.

Release verification

Each public release ships deterministic archives, checksums.txt, checksums.json, a Homebrew formula, release-provenance.json, and sbom.spdx.json. The public workflow also creates GitHub artifact attestations.

gh release download vX.Y.Z --repo ehmo/gomoufox --dir /tmp/gomoufox-vX.Y.Z
cd /tmp/gomoufox-vX.Y.Z
shasum -a 256 -c checksums.txt
gh attestation verify gomoufox_X.Y.Z_darwin_arm64.tar.gz -R ehmo/gomoufox

Maintainers also run the bundled public audit after publication:

python3 scripts/audit-public-release.py \
  --version vX.Y.Z \
  --repo ehmo/gomoufox \
  --verify-attestations \
  --brew-mode inspect

Common questions

Do I still need Python?

Yes, for the managed Camoufox runtime. gomoufox install creates the venv and pins the Camoufox package. node-direct changes the long-lived sidecar process, not the launch-options source of truth. Your application code can stay in Go.

Can gomoufox remove the Python dependency?

Not safely yet. Camoufox's Python launch_options path generates BrowserForge fingerprints, geoip and locale settings, WebGL/font/canvas values, Firefox preferences, and the final browser payload. That payload changes between launches. gomoufox does not cache it because stale fingerprints are a detection risk. A replacement needs either an upstream stable launch-plan contract or a parity-gated Go implementation against the pinned Camoufox package.

The removal track starts with a launch-plan audit:

go run ./cmd/gomoufox-launchplan --scenario all --out dist/launch-plan/latest

That command dumps gomoufox's Go launch input beside the Python Camoufox launch payload. It can also compare an optional future pure-Go candidate payload with --candidate <json> and fails on drift. Until that candidate exists and passes real-site plus fingerprint gates, Python stays required.

Why use gomoufox instead of Python Camoufox directly?

Use gomoufox when you need a typed Go API, a scriptable CLI, MCP tools for agents, release-gated Go/Python parity checks, and local URL guardrails. Use Python Camoufox directly when your project is already Python-first and does not need those surfaces.

Will every protected site work?

No. gomoufox tests against Python Camoufox on the same target set. A Go-only block or failure is a gomoufox regression. A shared block means both stacks saw the same site behavior during that run. Site policy, traffic reputation, browser changes, and upstream Camoufox changes can still affect results.

Where does browser state live?

Temporary sessions use temporary profile data. Persistent sessions use the directory you pass with --profile. MCP session import, export, proxy use, and file upload stay disabled until you start MCP with the matching operator flags.

Does MCP trust page content?

No. Browser-derived MCP responses carry provenance.trust: "untrusted". Agents should treat page text as data from the site, not instructions from the operator.

Can I run headful on Linux?

Yes, if a display exists. Set GOMOUFOX_AUTO_DISPLAY=1 when you want gomoufox to use an automatic display helper.

How do I debug install issues?

Run:

gomoufox doctor
gomoufox doctor --json
gomoufox --verbose doctor

Check GOMOUFOX_CAMOUFOX_PATH only when you intentionally bypass the managed runtime. Offline browser paths are manifest-verified unless GOMOUFOX_TRUST_UNVERIFIED_CAMOUFOX_PATH=1 is set for a trusted local build.

Compatibility

gomoufox pins the browser stack. Upgrade these pieces together.

gomoufox	playwright-go	Playwright in venv	Camoufox package	Camoufox browser
v0.1.x	v0.5700.1	1.57.0	0.4.11	v135.0.1-beta.24

Auto-fetch support is verified for macOS arm64. Other platforms may work with a pre-provisioned browser directory through GOMOUFOX_CAMOUFOX_PATH.

Headful Linux runs need an existing display or GOMOUFOX_AUTO_DISPLAY=1.

Development

go test -count=1 ./...
go test -race -count=1 ./...
go vet ./...
python3 scripts/check-agent-contracts.py
python3 scripts/format-doc-numbers.py
python3 scripts/update-python-locks.py --check --skip-pip-validate
go run golang.org/x/vuln/cmd/govulncheck@v1.3.0 ./...

Agent-facing CLI and MCP discovery snapshots live in docs/agent-contracts/. When CLI help or MCP tool schemas change, run python3 scripts/check-agent-contracts.py --update and review the diff.

Run python3 scripts/format-doc-numbers.py --write after editing docs with large displayed numbers.

The public repo is generated. Do not edit generated public files by hand.

License

gomoufox is MIT licensed.

Camoufox is MPL-2.0. gomoufox starts Camoufox as a subprocess and downloads its browser binary at runtime. gomoufox does not vendor or modify Camoufox.