Post-Quantum Cryptography MCP Server

A Model Context Protocol (MCP) server that provides post-quantum cryptographic operations using Open Quantum Safe's liboqs. Enables AI assistants like Claude to perform quantum-resistant cryptographic operations including key generation, encryption, signing, and verification.

Why Post-Quantum Cryptography?

Current cryptographic systems (RSA, ECC, ECDSA) will be broken by quantum computers running Shor's algorithm. NIST has standardized new quantum-resistant algorithms:

Standard	Algorithm	Type	Status
FIPS 203	ML-KEM (Kyber)	Key Encapsulation	Finalized 2024
FIPS 204	ML-DSA (Dilithium)	Digital Signature	Finalized 2024
FIPS 205	SLH-DSA (SPHINCS+)	Hash-based Signature	Finalized 2024

This MCP server makes these algorithms accessible to AI agents for research, development, and integration.

Features

• 32 Key Encapsulation Mechanisms (KEMs): ML-KEM, FrodoKEM, HQC, BIKE, Classic McEliece
• 221 Signature Algorithms: ML-DSA, Falcon, SPHINCS+, MAYO, CROSS, UOV
• Full MCP Integration: Works with Claude Desktop, Claude Code, Cursor, and any MCP client
• NIST Standards Compliant: Implements FIPS 203, 204, and 205 algorithms
• Security Analysis: Compare classical vs quantum security levels

Quick Start

Prerequisites

• Python 3.10+
• liboqs shared library
• uv (recommended) or pip

Installation

1. Install liboqs

macOS (Homebrew with shared library):

# Homebrew only provides static library, build from source for shared:
git clone --depth 1 --branch 0.15.0 https://github.com/open-quantum-safe/liboqs.git
cd liboqs && mkdir build && cd build
cmake -DBUILD_SHARED_LIBS=ON -DCMAKE_INSTALL_PREFIX=$HOME/.local ..
make -j4 && make install

Ubuntu/Debian:

sudo apt-get install liboqs-dev

2. Clone and Install

git clone https://github.com/scottdhughes/post-quantum-mcp.git
cd post-quantum-mcp

# Create virtual environment with Python 3.10+
uv venv --python 3.10 .venv
source .venv/bin/activate

# Install dependencies
uv pip install liboqs-python "mcp>=1.0.0"

3. Configure Claude Code / Claude Desktop

Add to your MCP configuration:

Claude Code (~/.claude.json):

{
  "mcpServers": {
    "pqc": {
      "type": "stdio",
      "command": "/path/to/post-quantum-mcp/run.sh",
      "args": [],
      "env": {}
    }
  }
}

Claude Desktop (claude_desktop_config.json):

{
  "mcpServers": {
    "pqc": {
      "command": "/path/to/post-quantum-mcp/run.sh"
    }
  }
}

Available Tools

pqc_list_algorithms

List all available post-quantum algorithms.

Input: { "type": "kem" | "sig" | "all" }
Output: List of available algorithms with NIST standard mappings

pqc_algorithm_info

Get detailed information about a specific algorithm.

Input: { "algorithm": "ML-KEM-768" }
Output: Key sizes, security level, performance characteristics

pqc_generate_keypair

Generate a quantum-resistant key pair.

Input: { "algorithm": "ML-DSA-65" }
Output: Base64-encoded public and secret keys

pqc_encapsulate

Perform key encapsulation (create shared secret).

Input: { "algorithm": "ML-KEM-768", "public_key": "<base64>" }
Output: Ciphertext and shared secret

pqc_decapsulate

Recover shared secret from ciphertext.

Input: { "algorithm": "ML-KEM-768", "secret_key": "<base64>", "ciphertext": "<base64>" }
Output: Shared secret

pqc_sign

Sign a message with a post-quantum signature.

Input: { "algorithm": "ML-DSA-65", "secret_key": "<base64>", "message": "Hello, quantum world!" }
Output: Base64-encoded signature

pqc_verify

Verify a post-quantum signature.

Input: { "algorithm": "ML-DSA-65", "public_key": "<base64>", "message": "...", "signature": "<base64>" }
Output: { "valid": true/false }

pqc_hash_to_curve

Hash a message using quantum-safe hash functions.

Input: { "message": "data", "algorithm": "SHA3-256" | "SHA3-512" | "SHAKE128" | "SHAKE256" }
Output: Digest in hex and base64

pqc_security_analysis

Analyze security properties of an algorithm.

Input: { "algorithm": "ML-KEM-768" }
Output: NIST level, classical/quantum security equivalents, Grover/Shor resistance

Supported Algorithms

Key Encapsulation Mechanisms (KEMs)

Algorithm	NIST Level	Public Key	Ciphertext	Shared Secret
ML-KEM-512	1	800 B	768 B	32 B
ML-KEM-768	3	1,184 B	1,088 B	32 B
ML-KEM-1024	5	1,568 B	1,568 B	32 B
FrodoKEM-640	1	9,616 B	9,720 B	16 B
HQC-128	1	2,249 B	4,481 B	64 B

Digital Signatures

Algorithm	NIST Level	Public Key	Signature	Notes
ML-DSA-44	2	1,312 B	2,420 B	Balanced
ML-DSA-65	3	1,952 B	3,309 B	Recommended
ML-DSA-87	5	2,592 B	4,627 B	High security
Falcon-512	1	897 B	653 B	Smallest sigs
Falcon-1024	5	1,793 B	1,280 B	Compact
SPHINCS+-SHA2-128f	1	32 B	17,088 B	Stateless, hash-based
SPHINCS+-SHA2-256f	5	64 B	49,856 B	Maximum security

Example Usage with Claude

Once configured, you can ask Claude:

"Generate an ML-KEM-768 keypair and show me the security analysis"

"Sign the message 'Hello quantum world' using ML-DSA-65 and verify it"

"Compare the signature sizes of Falcon-512 vs SPHINCS+-SHA2-128f"

"What's the quantum security level of ML-KEM-1024?"

Architecture

post-quantum-mcp/
├── pqc_mcp_server/
│   ├── __init__.py      # Main MCP server implementation
│   └── __main__.py      # Entry point
├── run.sh               # Wrapper script (sets DYLD_LIBRARY_PATH)
├── pyproject.toml       # Package configuration
└── README.md

Security Considerations

• Key Storage: This server generates keys in memory. For production use, implement secure key storage.
• Side Channels: liboqs implementations aim to be constant-time but may not be suitable for all threat models.
• Algorithm Selection: ML-KEM and ML-DSA are NIST-approved. Other algorithms are experimental.
• Version Compatibility: Ensure liboqs version matches liboqs-python expectations.

Development

# Run tests
python -m pytest tests/

# Format code
python -m black pqc_mcp_server/

# Type checking
python -m mypy pqc_mcp_server/

Related Projects

• Open Quantum Safe - The liboqs library
• Model Context Protocol - MCP specification
• quantum-proof-bitcoin - Bitcoin with PQC signatures

Contributing

Contributions are welcome! Please read CONTRIBUTING.md for guidelines.

License

MIT License - see LICENSE for details.

Acknowledgments

• Open Quantum Safe Project for liboqs
• Anthropic for the Model Context Protocol
• NIST for PQC standardization efforts