airmail-mcp: Instructions file for Codex

AGENTS.md

airmail-mcp AGENTS.md is an instructions file for Codex, OpenCode from Airmail/airmail-mcp. It costs 508 tokens per session, scanned A, original, MIT.

Repository instructions for airmail-mcp, a small Node.js bridge that forwards MCP requests to Airmail’s local native server.

In plain words
What is it for?
Use them when developing, building, synchronizing tools, or releasing the airmail-mcp bridge.
Why use it?
They document the project layout, build and release commands, coding conventions, and testing expectations so changes fit the repository and use its intended workflow.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: mentions CLAUDE.md; mentions AGENTS.md.

This is Airmail/airmail-mcp's own configuration. It tells Codex and OpenCode how to work on airmail-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything airmail-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to Airmail/airmail-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/Airmail/airmail-mcp/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/Airmail/airmail-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 airmail-mcp AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/airmail/airmail-mcp/agents-md.svg)](https://agentmods.dev/instructions/airmail/airmail-mcp/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/airmail/airmail-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/airmail/airmail-mcp/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 508 This file is loaded in full into every session.
When invoked 508 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00508 $0.00508
Opus 5 $0.00254 $0.00254
Sonnet 5 $0.00102 $0.00102
Haiku 4.5 $0.00051 $0.00051

Measured 7d ago against content hash 11b7df121bb1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

airmail-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 7d 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 · 38 lines

How it starts

The opening of the file, as written. The whole thing — 38 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Repository Guidelines

Project Structure & Module Organization

This repository is a thin Node.js bridge between MCP clients and Airmail's native MCP server on localhost:9876. Keep the layout small and focused:

  • src/index.ts: the only runtime source file; handles stdio, auth lookup, process launch, and raw TCP/HTTP forwarding.
  • scripts/sync-tools.mjs: generates manifest.json from local Airmail Swift sources.
  • manifest.json: packaged tool metadata.
  • scripts/release.sh: release automation for version bump, push, and GitHub release.
  • logo.png, README.md, AGENTS.md, and CLAUDE.md: package metadata and contributor context.

Build output goes to dist/ and should be treated as generated code.

Build, Test, and Development Commands

  • npm install: install the TypeScript toolchain.
  • npm run build: compile src/ to dist/ with tsc.
  • npm run watch: rebuild on file changes during local development.
  • npm run sync-tools: refresh manifest.json from the local Swift MCP source tree.
  • ./scripts/release.sh patch|minor|major: run the full release flow from main.

There is no npm test or npm run lint target in this repository. Do not document or add them unless the project introduces them first.

Coding Style & Naming Conventions

Use TypeScript with strict compiler settings and ES module syntax. Follow the existing file style in src/index.ts: double quotes, semicolons, concise helper functions, and clear constant names such as AIRMAIL_PORT and REQUEST_TIMEOUT_MS. Prefer small, direct changes in the single bridge entrypoint instead of introducing new abstractions without need.

Testing Guidelines

There is currently no automated test suite. For changes, verify by running npm run build and, when relevant, exercising the bridge locally against Airmail on macOS. Document any manual verification steps in the PR.

Commit & Pull Request Guidelines

Use short, imperative subjects and a body that explains behavior, release, or compatibility impact. Keep commit messages specific; avoid placeholder subjects like fix, update, or changes.

Read the full file on GitHub · 38 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. 7d ago First seen · 38 lines · 508 tokens per session scan A 11b7df121bb1

Subscribe to this mod's changes

airmail-mcp AGENTS.md is an instructions file published in the GitHub repository Airmail/airmail-mcp (6 stars, last pushed 1mo ago), licensed MIT. It adds 508 tokens to every session, about $0.0025 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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