Borrowing it
Nothing to install: this file belongs to PierfrancescoLijoi/mcp-brain. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/PierfrancescoLijoi/mcp-brain/main/CLAUDE.mdgit clone --depth 1 https://github.com/PierfrancescoLijoi/mcp-brainWrote 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.
[](https://agentmods.dev/instructions/pierfrancescolijoi/mcp-brain/claude-md)<a href="https://agentmods.dev/instructions/pierfrancescolijoi/mcp-brain/claude-md"><img src="https://agentmods.dev/badge/instructions/pierfrancescolijoi/mcp-brain/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.
<a href="https://agentmods.dev/instructions/pierfrancescolijoi/mcp-brain/claude-md"><img src="https://agentmods.dev/badge/instructions/pierfrancescolijoi/mcp-brain/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00837 | $0.00837 |
| Opus 5 | $0.00418 | $0.00418 |
| Sonnet 5 | $0.00167 | $0.00167 |
| Haiku 4.5 | $0.00084 | $0.00084 |
Grade A, and why
mcp-brain 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 9d 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.
How it starts
The opening of the file, as written. The whole thing — 91 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 project is
mcp-brain is a persistent memory MCP server for Claude Code. It stores project context, architectural decisions, and session snapshots in a local SQLite database (~/.mcp-brain/brain.db), then serves them back to Claude at the start of each session — eliminating context rebuilding overhead.
Commands
Install in editable mode:
pip install -e .
Run the server directly (dev):
python run.py
Run via installed entry point:
mcp-brain
There is no test suite or linter configured yet.
Architecture
Data model — three memory levels
Every memory has a computed score (0.0–1.0) that determines its level:
| Level | Score threshold | When loaded |
|---|---|---|
| L1 | ≥ 0.7 | Every session (brain_get_context) — ~70 tokens |
| L2 | ≥ 0.4 | On-demand (brain_get_decisions) — ~200–400 tokens |
| L3 | < 0.4 | Archive only, never served |
Scoring weights (src/brain/scorer.py): recency 35%, frequency 30%, file impact 20%, explicit flag 15%. Recency decays linearly to 0 over 30 days.
Request flow
Claude calls MCP tool
→ src/tools/mcp_tools.py (FastMCP tool definitions)
→ src/brain/retriever.py (business logic: scoring, level assignment)
→ src/brain/compressor.py (builds YAML context strings)
→ src/storage/db.py (SQLite reads/writes to ~/.mcp-brain/brain.db)
MCP tools (exposed to Claude)
| Tool | Purpose |
|---|---|
brain_init |
Register a project (call once per repo) |
brain_get_context |
Load L1 context — call at session start |
brain_get_decisions |
Load L2 decisions — call when historical context needed |
brain_remember |
Store a memory; level auto-assigned by scorer |
brain_save_session |
Save end-of-session snapshot (branch, wip, next steps) |
Memory categories: decision, avoid, pattern, failed.
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.
- 9d ago First seen · 91 lines · 837 tokens per session scan A c244c1fe1b0e
mcp-brain CLAUDE.md is an instructions file published in the GitHub repository PierfrancescoLijoi/mcp-brain (6 stars, last pushed 4mo ago), licensed MIT. It adds 837 tokens to every session, about $0.0042 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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