filesystem-mcp AGENTS.md

filesystem-mcp AGENTS.md is an instructions file for Codex, OpenCode from j0hanz/filesystem-mcp. It costs 170 tokens per session, scanned A, original, MIT.

Repository instructions for filesystem-mcp, a server that gives AI assistants guarded tools to read, write, search, compare, and edit files.

In plain words
What is it for?
Use it when checking, formatting, testing, fixing, or releasing the filesystem-mcp project.
Why use it?
It tells contributors which task commands to use and prevents manual version changes that could make release files disagree.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md.

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/j0hanz/filesystem-mcp/agents-md
Clone the repo
git clone --depth 1 https://github.com/j0hanz/filesystem-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 filesystem-mcp AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/j0hanz/filesystem-mcp/agents-md.svg)](https://agentmods.dev/instructions/j0hanz/filesystem-mcp/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/j0hanz/filesystem-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/j0hanz/filesystem-mcp/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 170 This file is loaded in full into every session.
When invoked 170 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 5.1 $0.00170 $0.00170
Opus 5 $0.00085 $0.00085
Sonnet 5 $0.00034 $0.00034
Haiku 4.5 $0.00017 $0.00017

Measured 6d ago against content hash 443b76d68241, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

filesystem-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 6d 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 · 24 lines

What it actually says

filesystem-mcp

MCP server exposing guarded filesystem tools (read, write, search, diff, patch) over stdio and Streamable HTTP.

Commands

Run checks through the task runner, not the npm scripts:

node scripts/tasks.mjs          # full repository check
node scripts/tasks.mjs fix      # format and lint-fix, then validate
node scripts/tasks.mjs --quick  # static checks only, no tests
node scripts/tasks.mjs test     # Node test runner; accepts native test flags

The task runner is a thin cross-platform wrapper over the npm scripts and Node's built-in test runner.

Releases

Versions are bumped by the Release workflow (workflow_dispatch), which keeps package.json and server.json in sync. Never hand-edit either version.

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. 6d ago First seen · 24 lines · 170 tokens per session scan A 443b76d68241

Subscribe to this mod's changes

filesystem-mcp AGENTS.md is an instructions file published in the GitHub repository j0hanz/filesystem-mcp (14 stars, last pushed 9d ago), licensed MIT. It adds 170 tokens to every session, about $0.0009 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 2026-08-30.