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.
npx agentmods add instructions/purplehat93/proton-mcp/agents-mdgit clone --depth 1 https://github.com/purplehat93/proton-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/purplehat93/proton-mcp/agents-md)<a href="https://agentmods.dev/instructions/purplehat93/proton-mcp/agents-md"><img src="https://agentmods.dev/badge/instructions/purplehat93/proton-mcp/agents-md.svg" alt="Measured on agentmods" 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 | $0.00469 | $0.00469 |
| Opus 5 | $0.00234 | $0.00234 |
| Sonnet 5 | $0.00094 | $0.00094 |
| Haiku 4.5 | $0.00047 | $0.00047 |
Grade A, and why
proton-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 5d 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 — 53 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
Keep this file short. Read the linked docs before changing architecture or behavior.
Before editing
- Read
ARCHITECTURE.md. - Read
docs/SPEC.mdfor tool contracts. - Read
SECURITY.mdbefore touching networking, credentials, Bridge integration, or write actions. - Read
docs/DEVELOPMENT.mdfor validation commands. - If the deployment repository
nmousouros/nas-infrastructureis available in the same workspace, read itsSTATE.mdandstacks/proton-mail/AGENTS.mdfor the current live deployment state. Do not copy changing runtime facts into this repository.
Repository boundary
This repository owns the MCP server implementation and its contracts. It does not own the live Synology deployment state or Proton Bridge image build.
Related repositories:
purplehat93/proton-bridge-docker— headless Proton Mail Bridge image.nmousouros/nas-infrastructure— live Compose deployment and current runtime handoff.
When a task spans repositories, inspect the relevant source rather than inferring behavior from deployment documentation.
Rules
- Controlled mailbox mutations require explicit user approval, bounded opaque ids, and the review/confirmation workflow. Do not add unattended mutation paths without an explicit safety design.
- Never expose Proton Mail Bridge IMAP/SMTP ports to the LAN or internet.
- Never commit Proton credentials, Bridge-generated credentials, tokens, keyrings, vault files, or mailbox data.
- Never add a generic shell/command-execution MCP tool.
- Prefer small, explicit MCP tools with bounded outputs.
- Metadata-first: do not fetch or return full message bodies unless the caller explicitly requests a message.
- Preserve existing tool schemas unless the task explicitly changes the contract.
- Do not redesign the two-container architecture without an explicit request.
- Runtime/deployment changes are not implied by source changes; do not assume permission to restart or modify the live NAS.
Validation
Before finishing a code change, run:
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.
- 5d ago First seen · 53 lines · 469 tokens per session scan A 833a6bbf1602
proton-mcp AGENTS.md is an instructions file published in the GitHub repository purplehat93/proton-mcp (0 stars, last pushed 6d ago), licensed MIT. It adds 469 tokens to every session, about $0.0023 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.
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).
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
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.
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.