What is ddb-mcp CLAUDE.md?

A CLAUDE.md instruction file for the ddb-mcp code repository. It documents the project structure, common commands, browser and browserless execution paths, and a character-data parser refactor.

Use it when working on ddb-mcp to find development commands, understand its architecture, locate character parser modules, and preserve its snapshot regression checks.

It gives coding agents repository-specific guidance, including how to build, test, lint, type-check, and safely change parsing behaviour.

How iamjameslennon/ddb-mcp configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to iamjameslennon/ddb-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/iamjameslennon/ddb-mcp/main/CLAUDE.md

Clone the repo

git clone --depth 1 https://github.com/iamjameslennon/ddb-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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/iamjameslennon/ddb-mcp/claude-md/github.svg)](https://agentmods.dev/instructions/iamjameslennon/ddb-mcp/claude-md)

Your own site

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

Per session 5,162 This file is loaded in full into every session.

When invoked 5,162 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 fork From a forked repository.

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	$0.05162	$0.05162
Opus 5	$0.02581	$0.02581
Sonnet 5	$0.01032	$0.01032
Haiku 4.5	$0.00516	$0.00516

Measured 8d ago against content hash 51523324482e, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

ddb-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 · 162 lines

How it starts

The opening of the file, as written. The whole thing — 162 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.

Note: The original 1000-line parseCharacterData has been carved into per-domain modules under src/tools/character/ (identity, vitals, ac, stats, defenses, features, weapons, actions, spells, inventory, notes, parse, definition). See docs/character-refactor.md for the module boundaries. When changing parse behaviour, keep the live-character snapshot regression flow listed there.

Commands

npm ci               # Install dependencies (prefer ci over install — respects the lockfile)
npm run dev          # Run in development mode (no build step, uses tsx)
npm run build        # Compile TypeScript to dist/
npm run build:watch  # Watch mode
npm run lint         # ESLint on the whole repo (src/, tests/, scripts/, root configs)
npm run typecheck    # Type-check without emitting
npm test             # Run all tests (vitest)
npm run release      # Bump version, generate release notes, publish (patch|minor|major)
                     #   accepts --dry-run (mutate files only, no commit/tag/push)
                     #   and --skip-verify (skip the `npm ci && npm test` gate)
npm run lobehub:manifest  # Regenerate lhm.plugin.json (needs dist/ — run build first)
npx vitest run tests/character-parser.test.ts  # Run a single test file

Architecture

This is a Model Context Protocol (MCP) server that exposes D&D Beyond data to Claude via stdio transport. Entry point: src/index.ts. All MCP tools are registered there and delegate to modules in src/tools/.

Two execution paths: browser vs. browserless

The central architectural split is between tools that need a Playwright browser and tools that work entirely through the saved session cookies:

Browserless (preferred) — src/session-fetch.ts

Reads cookies from a per-user config dir — ~/.config/ddb-mcp/session.json on macOS/Linux, %APPDATA%\ddb-mcp\session.json on Windows (written by ddb_login)
Exchanges cookies for a short-lived cobalt JWT via getCobaltToken()
All character, monster, spell, item, and condition tools use this path
sessionFetch() injects the cookie header into native Node fetch

Read the full file on GitHub · 162 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.

8d ago First seen · 162 lines · 5,162 tokens per session scan A 51523324482e

Subscribe to this mod's changes

ddb-mcp CLAUDE.md is an instructions file published in the GitHub repository iamjameslennon/ddb-mcp (1 stars, last pushed yesterday), licensed MIT. It adds 5,162 tokens to every session, about $0.0258 per session on Opus 5. A static security scan graded it A with 0 findings. It comes from a forked repository.

next.js AGENTS.md

AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.

vercel/next.js · 7,296 tokens

codex AGENTS.md

AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.

openai/codex · 5,153 tokens

vscode buildNext.instructions.md

Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

microsoft/vscode · 6,785 tokens

ddb-mcp: Instructions file for Claude Code