Borrowing it
Nothing to install: this file belongs to husniadil/ultrathink. 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/husniadil/ultrathink/main/CLAUDE.mdgit clone --depth 1 https://github.com/husniadil/ultrathinkWrote 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/husniadil/ultrathink/claude-md)<a href="https://agentmods.dev/instructions/husniadil/ultrathink/claude-md"><img src="https://agentmods.dev/badge/instructions/husniadil/ultrathink/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/husniadil/ultrathink/claude-md"><img src="https://agentmods.dev/badge/instructions/husniadil/ultrathink/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 | $0.02854 | $0.02854 |
| Opus 5.5 | $0.01142 | $0.01142 |
| Sonnet 5.5 | $0.00571 | $0.00571 |
| Haiku 4.5 | $0.00285 | $0.00285 |
Grade A, and why
ultrathink 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 2mo 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 — 369 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
UltraThink is an MCP (Model Context Protocol) server built with FastMCP framework. The project provides tools that can be consumed by MCP clients.
Development Commands
Setup & Dependencies
# Install dependencies (managed by uv)
uv sync
Task Commands (npm-like)
# List all tasks
uv run task --list
# Run server
uv run task run
# Run tests with coverage
uv run task test
# Quick tests (no coverage)
uv run task test-quick
# Run test client
uv run task client
# Format code (ruff + prettier)
uv run task format
# Lint code
uv run task lint
# Type check with mypy
uv run task typecheck
# Clean cache
uv run task clean
Direct Commands (Alternative)
Prefer using uv run task commands above. For direct execution:
# Run the server directly
uv run ultrathink
# Run the test client directly (connects to server via in-memory transport)
uv run task client
# Or: uv run python examples/client.py
This will test all available tools by connecting to the MCP server and calling each tool with sample inputs.
Architecture
Project Structure
src/ultrathink/ # Main package
├── models/ # DATA MODELS
│ ├── thought.py # Thought, ThoughtRequest, ThoughtResponse models
│ └── session.py # ThinkingSession model
├── services/ # BUSINESS LOGIC
│ └── thinking_service.py # UltraThinkService
├── interface/ # EXTERNAL INTERFACE
│ └── mcp_server.py # FastMCP server & tool registration
├── __init__.py # Package exports
└── __main__.py # CLI entry point
tests/ # Test files (100% coverage, mirroring source structure)
├── models/
│ ├── test_thought.py # Thought model tests
│ └── test_session.py # Session logging tests
├── services/
│ └── test_thinking_service.py # Service validation, functionality, branching, multi-session
├── interface/
│ └── test_mcp_server.py # MCP tool function tests
└── test_cli.py # CLI entry point tests
examples/ # Example/demo scripts
└── client.py # Test harness for the MCP server
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.
- 2mo ago First seen · 369 lines · 2,854 tokens per session scan A d2099dffbbe1
ultrathink CLAUDE.md is an instructions file published in the GitHub repository husniadil/ultrathink (21 stars, last pushed 6mo ago), licensed MIT. It adds 2,854 tokens to every session, about $0.0114 per session on Opus 5.5. 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 2026-08-30.
ultrathink CLAUDE.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| ultrathink CLAUDE.mdhusniadil/ultrathink | Instructions file | 21 | 6mo ago | MIT | A | 2,854 | Claude Code |
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