dgmo-mcp: Instructions file for Claude Code

CLAUDE.md

dgmo-mcp CLAUDE.md is an instructions file for Claude Code from diagrammo/dgmo-mcp. It costs 3,373 tokens per session, scanned A, original, MIT.

Instructions for dgmo-mcp, an MCP server that lets compatible coding tools create, check, and render DGMO diagrams. MCP is a standard way for AI clients to connect to external tools and servers.

In plain words
What is it for?
Use it when working on dgmo-mcp commands, transports such as stdio or HTTP, tests, formatting checks, trigger checks, or release preparation.
Why use it?
It explains how to build, test, validate, run, and release this diagram server correctly.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: mentions Claude Code.

This is diagrammo/dgmo-mcp's own configuration. It tells Claude Code how to work on dgmo-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything dgmo-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to diagrammo/dgmo-mcp. 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/diagrammo/dgmo-mcp/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/diagrammo/dgmo-mcp

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.

agentmods badge for dgmo-mcp CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/diagrammo/dgmo-mcp/claude-md.svg)](https://agentmods.dev/instructions/diagrammo/dgmo-mcp/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/diagrammo/dgmo-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/diagrammo/dgmo-mcp/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 3,373 This file is loaded in full into every session.
When invoked 3,373 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.03373 $0.03373
Opus 5 $0.01687 $0.01687
Sonnet 5 $0.00675 $0.00675
Haiku 4.5 $0.00337 $0.00337

Measured 8d ago against content hash 56de33cd5c0a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

dgmo-mcp 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 8d 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 · 70 lines

How it starts

The opening of the file, as written. The whole thing — 70 lines — stays where its author put it; the contents beside it link to each section on GitHub.

dgmo-mcp — @diagrammo/dgmo-mcp

The MCP server that gives Claude Code, Claude Desktop, Cursor and any MCP client the ability to author, validate and render DGMO — over stdio, or over streamable HTTP since 0.19.0. Published to npm as @diagrammo/dgmo-mcp, listed on the MCP registry as io.github.diagrammo/dgmo-mcp, and shipped as a .mcpb bundle on the GitHub release.

Commands

pnpm build            # tsup — 4 ESM entries + .d.ts
pnpm test             # vitest run
pnpm check:all        # deadcode + duplication + deps + test — what CI runs, and the gate before a release
pnpm check:triggers   # drift guard: triggers.json vs dgmo-content/registry.json — NOT in check:all, NOT in CI
./preflight.sh        # version sync, pack, fresh-install MCP probe. Runs on tag push (.githooks/pre-push). Runs NO tests
pnpm studio           # guidance studio (the README's `pnpm hub` / `pnpm harness` scripts do not exist)

The repo is prettier-clean, and check:all now enforces itformat:check runs first in the gate as of 2026-08-06, so pnpm format is safe to run bare and drift cannot accumulate again. It had: 47 files under tools/, tests/ and src/ were failing, and because nothing checked, one pnpm format during unrelated work turned an 8-file change into a 55-file one. If check:all fails on formatting, run pnpm format and commit that alone — never as a rider on a feature.

Depending on dgmo

It consumes the published @diagrammo/dgmo from npm, never the workspace checkout — there is no symlink here, unlike the app. Workspace dgmo edits are invisible until dgmo is published and the dep bumped, or until pnpm link ../dgmo (see CONTRIBUTING.md; pnpm install undoes it).

🔴 Since 2026-08-07 the library is a devDependency and is INLINED into the bundle (noExternal in tsup.config.ts), exactly as @diagrammo/dgmo-cli does it. Declaring it at runtime meant every install of this server — and every npm i -g @diagrammo/dgmo-cli, which spawns it — unpacked the library plus its d3, dagre and lz-string trees: 17,028 KB, on top of a CLI bundle that already inlines the same library and never loads that copy. A CLI install measured 73,956 KB before and 63,344 KB after.

Read the full file on GitHub · 70 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. 8d ago First seen · 70 lines · 3,373 tokens per session scan A 56de33cd5c0a

Subscribe to this mod's changes

dgmo-mcp CLAUDE.md is an instructions file published in the GitHub repository diagrammo/dgmo-mcp (3 stars, last pushed 3d ago), licensed MIT. It adds 3,373 tokens to every session, about $0.0169 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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