What is mycelium-hypha CLAUDE.md?

Repository instructions for Mycelium Hypha, a Claude plugin and knowledge-generation system for OMG SysML v2 and KerML standards. SysML v2 and KerML are languages used to describe complex systems and their structure.

Use them when changing the plugin, knowledge-generation pipelines, .NET tools, tests, or the rules for committed and generated files.

They explain which files belong to the plugin, which generate its knowledge base, and how builds and tests work, reducing confusion in a repository with two related systems.

How mycelium-cmbse/mycelium-hypha configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to mycelium-cmbse/mycelium-hypha. 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/mycelium-cmbse/mycelium-hypha/development/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/mycelium-cmbse/mycelium-hypha

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/mycelium-cmbse/mycelium-hypha/claude-md/github.svg)](https://agentmods.dev/instructions/mycelium-cmbse/mycelium-hypha/claude-md)

Your own site

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

Per session 3,098 This file is loaded in full into every session.

When invoked 3,098 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	$0.03098	$0.03098
Opus 5	$0.01549	$0.01549
Sonnet 5	$0.00620	$0.00620
Haiku 4.5	$0.00310	$0.00310

Measured yesterday against content hash b6199ca76c92, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

mycelium-hypha 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 yesterday.

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 · 182 lines

How it starts

The opening of the file, as written. The whole thing — 182 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.

What this repo is

Two things in one repository, scoped to the OMG SysML v2 / KerML standards (not UML):

The hypha Claude plugin — .claude-plugin/, skills/, agents/, commands/, hooks/, and the knowledge/ base the plugin reads at runtime. Nothing per-release under knowledge/ is committed (see "Committed vs git-ignored" below): a plugin install fetches and generates it on the user's own machine, on request.
The generation pipelines in tools/ that build knowledge/ from upstream OMG sources in sources/. The pipelines are not shipped with the plugin.

Build & test

.NET (tools/metamodel-gen, tools/knowledge-gen and tools/hypha-cli, net10.0, NUnit), from repo root:

dotnet build mycelium-hypha.sln
dotnet test mycelium-hypha.sln
dotnet test mycelium-hypha.sln --filter "FullyQualifiedName~MetamodelClosureTests"   # one fixture/test
dotnet test mycelium-hypha.sln --filter "TestCategory=Live"   # [Explicit]: really fetches from GitHub

Nothing reaches the network in a normal run. The Live category is [Explicit], so it is opt-in and never in CI; set GITHUB_TOKEN before running it (the anonymous API allows 60 requests an hour).

Python (tools/spec-extract, Python ≥ 3.12), from tools/spec-extract/:

python -m venv .venv && . .venv/Scripts/activate   # or source .venv/bin/activate
pip install -e .[dev]
ruff check .
pytest
pytest tests/test_clauses.py::test_detects_clauses_and_groups_body   # one test (or: pytest -k <expr>)

The CLI generates, the tests verify

Generation is driven by tools/hypha-cli (the hypha command), never by the test runner. No test writes into knowledge/ — running dotnet test leaves the working tree clean, and a test that dirties it is a bug.

dotnet run --project tools/hypha-cli/Hypha.Tools -- generate            # all artifacts, all releases
dotnet run --project tools/hypha-cli/Hypha.Tools -- generate metamodel --tag 2026-05
dotnet run --project tools/hypha-cli/Hypha.Tools -- fetch --tag 2026-05 # sources/<tag>/

Read the full file on GitHub · 182 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.

yesterday Changed · +2 lines · +67 tokens per session b6199ca76c92
9d ago First seen · 180 lines · 3,031 tokens per session scan A be0a8a254e7b

Subscribe to this mod's changes

mycelium-hypha CLAUDE.md is an instructions file published in the GitHub repository mycelium-cmbse/mycelium-hypha (11 stars, last pushed 2d ago), licensed Apache-2.0. It adds 3,098 tokens to every session, about $0.0155 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.

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mycelium-hypha: Instructions file for Claude Code