$ urandom-mcp | stdio▍

MCP server.

Cryptographically secure randomness and post-quantum keys for AI agents — over stdio JSON-RPC, no network port. Every tool runs locally; the only egress is opt-in.

Connect

// add to your MCP client config (e.g. mcpServers)
{
  "mcpServers": {
    "urandom": {
      "command": "urandom-mcp",
      "env": { "URANDOM_CHECK_ENABLE": "0" }
    }
  }
}

Transport is stdio (JSON-RPC 2.0); there is no port to open and nothing to TLS. Build it with cargo run -p urandom-mcp. The server advertises its tools and usage instructions on connect.

The ten tools

random_bytes — N cryptographically secure random bytes, hex-encoded.
random_int — uniform integer in an inclusive [min, max] range.
uuid — a random v4 UUID.
password — a high-entropy password of a given length.
entropy_health — sample entropy, run SP 800-90B health tests (RCT + APT).
mlkem768_keypair — ML-KEM-768 (FIPS 203) keypair, hex.
mldsa65_keypair — ML-DSA-65 (FIPS 204) signing keypair, hex.
mldsa65_sign — sign a message with an ML-DSA-65 secret key.
mldsa65_verify — verify an ML-DSA-65 signature.
check_key_exposure — privately check a key against the seen-key registry (verifiable OPRF). The only networked tool — disabled unless URANDOM_CHECK_ENABLE=1.

Safety model

No inbound network surface. Nine tools are pure-local computation. check_key_exposure is the sole egress: it stays disabled until URANDOM_CHECK_ENABLE=1, targets URANDOM_API_URL (default https://urandom.ai), and sends only a blinded point — never the key. Secret material is zeroized in memory and the whole workspace is forbid(unsafe_code). See the check protocol.