agentmods.dev

ff-mcp AGENTS.md

ff-mcp AGENTS.md is an instructions file for Codex, OpenCode from complynx/ff-mcp. It costs 544 tokens per session, scanned A, original, MIT.

An AGENTS.md instruction set for setting up ff-mcp, a tool that connects an agent to Firefox. It defines setup steps, safety limits, and required user confirmations.

In plain words
What is it for?
For guiding ff-mcp installation and Firefox setup while checking software versions, selecting a profile, and preserving security boundaries.
Why use it?
It prevents guessing the Firefox profile and helps avoid exposing tokens, changing system settings, or granting access without approval.

Instructions file for CodexOpenCode

not rated 0 3d ago A scan 544 tokens original MIT
View the source file complynx/ff-mcp
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/complynx/ff-mcp/agents-md
Clone the repo
git clone --depth 1 https://github.com/complynx/ff-mcp

Made for: Codex, OpenCode.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for ff-mcp AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/complynx/ff-mcp/agents-md.svg)](https://agentmods.dev/instructions/complynx/ff-mcp/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/complynx/ff-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/complynx/ff-mcp/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 544 This file is loaded in full into every session.
When invoked 544 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00544 $0.00544
Opus 5 $0.00272 $0.00272
Sonnet 5 $0.00109 $0.00109
Haiku 4.5 $0.00054 $0.00054

Measured 3d ago against content hash 37add7c48350, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

ff-mcp AGENTS.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

AGENTS.md · 52 lines

How it starts

The opening of the file, as written. The whole thing — 52 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Agent rules

Goal: set up local ff-mcp from repo. Full runbook: docs/agent-setup.md. User guide: docs/user-setup.md.

Hard limits

  • Need explicit user profile choice. Never guess profile.
  • Ask before system-software install, GUI launch, shell-startup edit, or client-config edit outside repo.
  • Firefox confirmation stays. Never sideload into profile or auto-grant capability.
  • Token stays private. Never run ff-mcp connection --show-token in captured tool output.
  • Never commit token, print token, paste token, or bind MCP outside loopback.
  • Do not run ff-mcp serve. Firefox starts native host.

Setup

  1. Check OS, Firefox 150+, Python 3.14, uv.

  2. Run uv tool install --force ..

  3. If command missing: run uv tool dir --bin; use absolute binary. Ask before uv tool update-shell.

  4. Run ff-mcp profiles --json.

  5. Show profiles. Ask user for exact path.

  6. Ask before Firefox launch.

  7. Run:

    ff-mcp setup --profile "/exact/profile/path" --install-addon --json

  8. User confirms Firefox install. User opens popup and presses Start.

  9. Snap/Flatpak may show portal prompt. User approves.

  10. User privately runs ff-mcp connection --show-token and sets FF_MCP_TOKEN.

  11. Configure chosen client from runbook. Ask before external config write.

  12. Verify tool list, browser_tabs, approved READ, then browser_revoke.

No profile found: user opens about:profiles, copies Root Directory, gives exact path.

Launch fails: run --download-addon; give XPI path. User installs through about:addons → gear → Install Add-on From File….

Checks

UV_CACHE_DIR=/tmp/ff-mcp-uv-cache uv sync --locked --group dev
UV_CACHE_DIR=/tmp/ff-mcp-uv-cache uv run ruff check .
UV_CACHE_DIR=/tmp/ff-mcp-uv-cache uv run ruff format --check .
UV_CACHE_DIR=/tmp/ff-mcp-uv-cache uv run pytest -q
node --test tests/background.test.js tests/content.test.js tests/policy.test.js tests/rule-model.test.js

Read the full file on GitHub · 52 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 52 lines · 544 tokens per session scan A 37add7c48350

Subscribe to this mod's changes

ff-mcp AGENTS.md is an instructions file published in the GitHub repository complynx/ff-mcp (0 stars, last pushed 3d ago), licensed MIT. It adds 544 tokens to every session, about $0.0027 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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