second-brain-mcp: Instructions file for Claude Code

CLAUDE.md

second-brain-mcp CLAUDE.md is an instructions file for Claude Code from VoCoufi/second-brain-mcp. It costs 1,193 tokens per session, scanned B, original, MIT.

Project instructions for a Model Context Protocol (MCP) server that stores and searches structured notes from coding sessions.

In plain words
What is it for?
Use them when installing dependencies, building TypeScript into JavaScript, running the server, or changing its note-capture and search tools.
Why use it?
They give contributors the commands, architecture, and build rules needed to develop and test the server correctly.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: reads .claude/ paths; mentions CLAUDE.md; mentions Claude Code.

This is VoCoufi/second-brain-mcp's own configuration. It tells Claude Code how to work on second-brain-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 second-brain-mcp configures →

Not installable: its command points at a path on the author’s own machine, so it runs nowhere else. The line is /home/user/notes.

Reuse

Borrowing it

Nothing to install: this file belongs to VoCoufi/second-brain-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/VoCoufi/second-brain-mcp/master/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/VoCoufi/second-brain-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 second-brain-mcp CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/vocoufi/second-brain-mcp/claude-md/github.svg)](https://agentmods.dev/instructions/vocoufi/second-brain-mcp/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/vocoufi/second-brain-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/vocoufi/second-brain-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.

agentmods 80×15 button for second-brain-mcp CLAUDE.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/vocoufi/second-brain-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/vocoufi/second-brain-mcp/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 1,193 This file is loaded in full into every session.
When invoked 1,193 The same file — it is already loaded in full.
Security scan B 1 finding. 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 $0.01193 $0.01193
Opus 5 $0.00596 $0.00596
Sonnet 5 $0.00239 $0.00239
Haiku 4.5 $0.00119 $0.00119

Measured 8d ago against content hash 3b6f2285d480, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade B, and why

second-brain-mcp CLAUDE.md scanned grade B with 1 finding 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.

Reads agent configuration directoriesmediumAgent snooping

.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.

2. Configure in Claude Code settings at `~/.claude/settings.local.json`:
CLAUDE.md · 118 lines

How it starts

The opening of the file, as written. The whole thing — 118 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.

Project Overview

This is an MCP (Model Context Protocol) server that captures structured markdown notes from Claude Code sessions. It automatically analyzes sessions with pattern detection and simple complexity analysis, and provides unified search/discovery features across all notes.

Build & Development Commands

# Install dependencies
pnpm install

# Build TypeScript → JavaScript (output: build/)
pnpm run build

# Watch mode (auto-rebuild on changes)
pnpm run watch

# Run server locally (builds first)
pnpm run dev

After making changes: Always run pnpm run build before testing the MCP server with Claude Code, as MCP servers execute from build/index.js, not source files.

Architecture

Entry Point & Server Setup

  • src/index.ts: MCP server implementation using @modelcontextprotocol/sdk
    • Registers 3 tools (capture_session_note, search_notes, generate_weekly_report)
    • Handles tool execution via CallToolRequestSchema handler
    • Runs on stdio transport (communicates via stdin/stdout)

Core Data Flow (capture_session_note)

  1. Receive: SessionNote data (summary, commands, fileChanges, codeSnippets, tags, etc.)
  2. Analyze:
    • Pattern detection (new-feature, bug-fix, refactoring, etc.) via patternDetector.ts
    • Simple complexity analysis (simple/moderate/complex) based on file count via analysisUtils.ts
    • Key file extraction and key changes generation via analysisUtils.ts
  3. Format: Convert to markdown with emoji indicators via noteFormatter.ts
  4. Save: Markdown file + metadata JSON via storage.ts

Service Modules (src/services/)

  • storage.ts: File operations - saves notes to ~/notes/ (or $SECOND_BRAIN_NOTES_DIR), organized by project subdirectories. Creates .meta.json cache files for fast queries.

  • noteFormatter.ts: Converts SessionNote objects to markdown with emoji indicators, collapsible sections, and Key Changes bullets.

Read the full file on GitHub · 118 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 · 118 lines · 1,193 tokens per session scan B 3b6f2285d480

Subscribe to this mod's changes

second-brain-mcp CLAUDE.md is an instructions file published in the GitHub repository VoCoufi/second-brain-mcp (3 stars, last pushed 9mo ago), licensed MIT. It adds 1,193 tokens to every session, about $0.0060 per session on Opus 5. A static security scan graded it B with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other instructions, from other repositories

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

vscode oss-third-party-notices.instructions.md

Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).

microsoft/vscode · 5,001 tokens

langchain AGENTS.md

AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.

langchain-ai/langchain · 4,469 tokens

spec-kit AGENTS.md

AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.

github/spec-kit · 7,104 tokens