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/citizen4our/arch-mcp-server/agents-mdgit clone --depth 1 https://github.com/Citizen4our/arch-mcp-serverWrote 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/citizen4our/arch-mcp-server/agents-md)<a href="https://agentmods.dev/instructions/citizen4our/arch-mcp-server/agents-md"><img src="https://agentmods.dev/badge/instructions/citizen4our/arch-mcp-server/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 | $0.02305 | $0.02305 |
| Opus 5 | $0.01153 | $0.01153 |
| Sonnet 5 | $0.00461 | $0.00461 |
| Haiku 4.5 | $0.00231 | $0.00231 |
Grade A, and why
arch-mcp-server 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 — 254 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
Project Overview
This is a Rust-based Model Context Protocol (MCP) server that provides tools, prompts, and resources for AI agents. The project uses the rmcp library to implement MCP server functionality with HTTP transport, supporting tools, prompts, and resource management for AI agent interactions.
Build and Development Commands
Standard Rust Commands
- Build:
cargo build - Build release:
cargo build --release - Check:
cargo check - Test:
cargo test - Run:
cargo run - Format:
cargo fmt - Clippy:
cargo clippy
Development Server
- Run server:
cargo run --release(starts on 127.0.0.1:8010) - Test MCP connection: Connect to
http://127.0.0.1:8010/mcp
Important: Do NOT run cargo run automatically
- NEVER run
cargo runorcargo run --releasewithout explicit user request - Only run compilation commands:
cargo check,cargo build,cargo test - Server startup should only happen when user explicitly asks for it
Testing Commands
- Run all tests:
cargo test - Run with output:
cargo test -- --nocapture - Test specific module:
cargo test counter
Code Quality Guidelines
Critical Thinking Checklist (MANDATORY)
Before proposing any solution, complete this checklist:
- Question the problem itself: Is the complexity actually necessary? Can we eliminate the need entirely?
- Find the simplest possible solution first: What would require the least code changes to solve this?
- Challenge every assumption: Why does the current code work this way? Is it still relevant?
- Look at actual usage: How is this code really used? Can we optimize for the common cases?
- Design the API before implementation: What would be the cleanest interface for this functionality?
Problem-Solving Priority Order (MUST follow in sequence):
- ELIMINATE - Can we remove the problem entirely by restructuring?
- SIMPLIFY - Can we solve this trivially by changing the approach?
- REUSE - Does existing code already solve this?
- Only then: CREATE - Write new solution only if above options fail
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 · 254 lines · 2,305 tokens per session scan A 2ff929862fd0
arch-mcp-server AGENTS.md is an instructions file published in the GitHub repository Citizen4our/arch-mcp-server (2 stars, last pushed 4mo ago), licensed MIT. It adds 2,305 tokens to every session, about $0.0115 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
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.
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 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).
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.
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 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).