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.
curl -O https://raw.githubusercontent.com/Airmail/airmail-mcp/main/AGENTS.mdgit clone --depth 1 https://github.com/Airmail/airmail-mcpWrote 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.
[](https://agentmods.dev/instructions/airmail/airmail-mcp/agents-md)<a href="https://agentmods.dev/instructions/airmail/airmail-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/airmail/airmail-mcp/agents-md/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<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="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00508 | $0.00508 |
| Opus 5.5 | $0.00203 | $0.00203 |
| Sonnet 5.5 | $0.00102 | $0.00102 |
| Haiku 4.5 | $0.00051 | $0.00051 |
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 2mo 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.
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: generatesmanifest.jsonfrom 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, andCLAUDE.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: compilesrc/todist/withtsc.npm run watch: rebuild on file changes during local development.npm run sync-tools: refreshmanifest.jsonfrom the local Swift MCP source tree../scripts/release.sh patch|minor|major: run the full release flow frommain.
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.
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.
- 2mo ago First seen · 38 lines · 508 tokens per session scan A 11b7df121bb1
airmail-mcp AGENTS.md is an instructions file published in the GitHub repository Airmail/airmail-mcp (7 stars, last pushed 3mo ago), licensed MIT. It adds 508 tokens to every session, about $0.0020 per session on Opus 5.5. 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.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).
deepseek-harness AGENTS.md
AGENTS.md instructions for deepseek-ai/deepseek-harness, covering agents.md, pre-stable apis and released session data, repository layout, commands and host sandbox failures.