What is registry CLAUDE.md?

A project instruction file for Claude Code in the Model Context Protocol server registry. It explains how to handle the project's instructions and publish MCP servers, which are services that give agents extra tools or information.

Use it when developing the registry or preparing MCP servers for publication with Claude Code.

It gives Claude Code project-specific guidance instead of relying only on general coding habits.

How modelcontextprotocol/registry configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to modelcontextprotocol/registry. 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/modelcontextprotocol/registry/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/modelcontextprotocol/registry

Made for: Claude Code.

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/modelcontextprotocol/registry/claude-md/github.svg)](https://agentmods.dev/instructions/modelcontextprotocol/registry/claude-md)

Your own site

<a href="https://agentmods.dev/instructions/modelcontextprotocol/registry/claude-md"><img src="https://agentmods.dev/badge/instructions/modelcontextprotocol/registry/claude-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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/modelcontextprotocol/registry/claude-md"><img src="https://agentmods.dev/badge/instructions/modelcontextprotocol/registry/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 225 This file is loaded in full into every session.

When invoked 225 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 unknown 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.

Model	Per session	Once invoked
Fable 5.1	$0.00225	$0.00225
Opus 5.5	$0.00090	$0.00090
Sonnet 5.5	$0.00045	$0.00045
Haiku 4.5	$0.00022	$0.00022

Measured 26d ago against content hash b02f42a74b0e, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

registry 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 26d 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 · 13 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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.

26d ago Changed · +2 lines · +91 tokens per session b02f42a74b0e
2mo ago First seen · 11 lines · 134 tokens per session scan A 72da2a04d405

Subscribe to this mod's changes

registry CLAUDE.md is an instructions file published in the GitHub repository modelcontextprotocol/registry (7,445 stars, last pushed yesterday), with no licence file. It adds 225 tokens to every session, about $0.0009 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 2026-08-30.

mcp mcp-servers

registry CLAUDE.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
registry CLAUDE.mdmodelcontextprotocol/registry	Instructions file	7.4k	yesterday	none	A	225	Claude Code
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	today	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	today	MIT	A	4,680	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	today	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

registry: Instructions file for Claude Code