MCP Server

@openreason/mcp is a Model Context Protocol server that gives any AI agent native OpenReason capabilities: validate an ORP document, verify its cryptographic attestation offline, and explain the protocol. It wraps the JavaScript SDK and speaks stdio, so it plugs into Claude Desktop, Claude Code, Cursor and any other MCP host without extra infrastructure.

Run

No install needed:

npx -y @openreason/mcp

Or build from source: git clone https://github.com/openreasonprotocol/openreason.git, then npm install && npm run build in sdk-js/ and mcp/; the binary is mcp/dist/index.js.

Connect an agent

Add the server to your MCP host configuration. For Claude Desktop (claude_desktop_config.json) or Claude Code (.mcp.json):

{
  "mcpServers": {
    "openreason": {
      "command": "npx",
      "args": ["-y", "@openreason/mcp"]
    }
  }
}

On start the server logs openreason-mcp: ready on stdio to stderr and exposes three tools.

Tools

orp_validate

Validate an ORP document (JSON or YAML string). Returns the compliance level, which of the five layers are present, and any errors or warnings.

{ "document": "orp_version: \"0.2\"\n..." }

Bundles the v0.1 and v0.2 schemas today; v0.3 profile validation is available through the Python validator and REST API.

orp_verify_attestation

Cryptographically verify a v0.3 document’s attestation offline: recompute the canonical hash and check the Ed25519 signatures. Returns validity, the trust tier, the computed hash, and a per-signature verdict.

{
  "document": "...",
  "keys": { "publisher-2026": "did:key:z6Mk..." }
}

keys maps a signature kid to key material (a did:key, a base64url raw key, or a JWK x value). A kid that is itself a did:key resolves without the map. Unknown keys fail closed.

orp_explain

Plain-language explanation of a protocol concept for the agent’s own reasoning. topic is one of overview, layers, trust-tiers, attestation, compliance.

Why an agent needs this

An agent deciding in milliseconds whether to rely on a claim cannot read a PDF. With these tools it can take a signed ORP object, verify who attested to it and under which key, read the trust tier, and act under its own mandate, without trusting the publisher or OpenReason. That is the machine half of the dual reader the protocol is built for.

See also

• JavaScript SDK — the library the server wraps
• REST API — hosted validation for hosts that cannot run a local process