mcp-chat CLAUDE.md

mcp-chat CLAUDE.md is an instructions file for coding agents from hbd/mcp-chat. It costs 595 tokens per session, scanned A, original, MIT.

Repository instructions for MCP Chat, a Python server that lets people talk through MCP tool calls. They cover setup, package management, framework conventions, and code checks.

In plain words
What is it for?
Use it when installing dependencies, changing the MCP server, or checking Python code with uv, mypy, and Ruff.
Why use it?
It gives the coding agent the project rules in one place, reducing setup mistakes and inconsistent code changes.

Instructions file

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/hbd/mcp-chat/claude-md
Clone the repo
git clone --depth 1 https://github.com/hbd/mcp-chat

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.

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README.md
[![agentmods](https://agentmods.dev/badge/instructions/hbd/mcp-chat/claude-md.svg)](https://agentmods.dev/instructions/hbd/mcp-chat/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/hbd/mcp-chat/claude-md"><img src="https://agentmods.dev/badge/instructions/hbd/mcp-chat/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 595 This file is loaded in full into every session.
When invoked 595 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 $0.00595 $0.00595
Opus 5 $0.00298 $0.00298
Sonnet 5 $0.00119 $0.00119
Haiku 4.5 $0.00060 $0.00060

Measured 4d ago against content hash e0df58ab2484, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

mcp-chat CLAUDE.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 4d 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.

CLAUDE.md · 85 lines

How it starts

The opening of the file, as written. The whole thing — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Project Overview

MCP Chat is a Python-based MCP (Model Context Protocol) server that enables direct chat between users through MCP tool calls. It demonstrates using MCP's tool-calling interface for real-time human communication.

Development Setup

This is a Python project using the following tools and conventions:

Package Management

  • uv: Use uv for all package management tasks
    • Install dependencies: uv sync
    • Add new dependencies: uv add <package>
    • Create virtual environment: uv venv

MCP Framework

  • FastMCP: This project uses the FastMCP framework for building the MCP server
    • Follow FastMCP conventions for handlers and server setup
    • Use FastMCP's built-in decorators and utilities

Code Quality Tools

  • mypy: Type checking

    • Run with: mypy .
    • Ensure all code has proper type annotations
    • Fix all type errors before committing
  • Ruff: Linting and formatting

    • Format code: ruff format .
    • Lint code: ruff check .
    • Fix linting issues: ruff check --fix .
    • Always run both before committing changes

Development Commands

# Set up environment
uv venv
source .venv/bin/activate  # On Unix/macOS
# or
.venv\Scripts\activate  # On Windows

# Install dependencies
uv sync

# Type checking
mypy .

# Linting and formatting
ruff format .
ruff check --fix .

# Run the MCP server
python -m mcp_chat.server

Project Structure

mcp-chat/
├── mcp_chat/
│   ├── __init__.py
│   ├── server.py          # Main MCP server entry point
│   ├── handlers/          # MCP request handlers
│   ├── matching/          # Interest matching algorithms
│   └── models/            # Data models and types
├── tests/
├── pyproject.toml         # Project configuration and dependencies
└── README.md

Code Conventions

  • Use type hints for all functions and class methods
  • Follow PEP 8 style guide (enforced by Ruff)
  • Write docstrings for all public functions and classes
  • Keep functions focused and single-purpose
  • Use descriptive variable and function names
  • Always use absolute import paths (e.g., from mcp_chat.models import User not from .models import User)

Read the full file on GitHub · 85 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. 4d ago First seen · 85 lines · 595 tokens per session scan A e0df58ab2484

Subscribe to this mod's changes

mcp-chat CLAUDE.md is an instructions file published in the GitHub repository hbd/mcp-chat (5 stars, last pushed 1y ago), licensed MIT. It adds 595 tokens to every session, about $0.0030 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.