What is muster CLAUDE.md?

A project instruction file for Muster, a control plane that combines multiple MCP servers and lets platform engineers and AI agents discover and use their tools. It also documents Muster’s build, test, lint, and Helm commands.

Use it while developing Muster, running its unit or behavior-driven tests, checking Go code quality, or validating Helm changes.

It gives coding agents the repository context and the commands needed to build, test, debug, format, and validate changes consistently.

How giantswarm/muster configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to giantswarm/muster. 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/giantswarm/muster/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/giantswarm/muster

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/giantswarm/muster/claude-md/github.svg)](https://agentmods.dev/instructions/giantswarm/muster/claude-md)

Your own site

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

Per session 3 This file is loaded in full into every session.

When invoked 3 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 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.

Model	Per session	Once invoked
Fable 5.1	$0.00003	$0.00003
Opus 5.5	$0.00001	$0.00001
Sonnet 5.5	$0.00001	$0.00001
Haiku 4.5	$0.00000	$0.00000

Measured 13d ago against content hash a54ff182c7e8, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

muster 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 13d 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 · 1 lines

What it actually says

AGENTS.md

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.

13d ago Changed · -85 lines · -962 tokens per session a54ff182c7e8
19d ago Changed · +12 tokens per session 644e8f8f62ef
26d ago Changed e9ca2a281fbd
2mo ago First seen · 86 lines · 953 tokens per session scan A dd13ce650ad9

Subscribe to this mod's changes

muster CLAUDE.md is an instructions file published in the GitHub repository giantswarm/muster (40 stars, last pushed yesterday), licensed Apache-2.0. It adds 3 tokens to every session, about $0.0000 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.

ai development development-tools mcp mcp-client mcp-proxy

muster CLAUDE.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
muster CLAUDE.mdgiantswarm/muster	Instructions file	40	yesterday	Apache-2.0	A	3	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

muster: Instructions file for Claude Code