Rubric Protocol

@rubric-protocol/mcp-server

Post-quantum AI compliance attestation as an MCP server. Works with Claude Desktop, Claude Code, Cursor, Windsurf, Continue, Zed, and any MCP-compatible host.

v2.0 — now with free local tier. No API key required to start attesting.

Install

npm install -g @rubric-protocol/mcp-server

Configure (Claude Desktop)

Edit claude_desktop_config.json:

{  "mcpServers": {    "rubric": {      "command": "npx",      "args": ["-y", "@rubric-protocol/mcp-server"],      "env": { "RUBRIC_API_KEY": "optional-for-hcs-anchoring" }    }  }}

Restart Claude Desktop. Rubric tools appear in the MCP menu.

Tiers

Free (no key)

• attest — PQ-signed Merkle leaves stored in ~/.rubric/local-bundles/
• verify — check local attestations
• framework_detect — detect applicable regulations offline
• cost_estimate — project monthly cost
• register_agent — request a free key to unlock HCS anchoring
• status — federation health

With API key (free developer tier)

Everything above, plus:

• HCS anchoring on Hedera mainnet (tamper-evident third-party timestamp)
• get_proof — ZK Merkle inclusion proofs (Noir/Barretenberg)

Request a key via the register_agent tool, or at https://rubric-protocol.com

Standard+ tier ($999/mo)

• compliance_tag — attach regulatory framework tags to bundles
• bundle_query — filter by leafType, agentId, time range
• 100K attestations/mo, overage $0.01 each

Enterprise ($9,999/mo) / Dedicated ($25K+/mo)

Higher throughput, SLA, dedicated federation capacity.

Paid evidence tools (x402) - new in 2.2

Six tools that pay per call in USDC on Base via the x402 protocol. No Rubric account or API key required - just a funded wallet. Every response carries a signed, Hedera-anchored attestation ID your agent can cite later.

Setup (3 steps)

1. Create a wallet and fund it with a few dollars of USDC on Base (Coinbase -> withdraw USDC -> network: Base)
2. Set RUBRIC_WALLET_KEY to the wallet's private key in your MCP server environment
3. Optional: RUBRIC_X402_DAILY_LIMIT (default 1.00 USD/day)

Money safety, by design

• No wallet key? Paid tools return setup guidance - never errors, never charges.
• Daily ceiling. Spending stops at your limit; the tool returns a budget error your agent can read. Resets 00:00 UTC.
• Price protection. Before paying, each tool checks the server's quoted price against its documented maximum and refuses anything higher - even we cannot overcharge you.
• Full accounting. Every paid response includes spentTodayUsd.
• Your key never leaves the MCP process. A failed operation is never charged.

Catalog, prices, and terms are machine-readable at x402.json and openapi.json.

Module configuration

Tools load by module via RUBRIC_MCP_MODULES (default: core,x402). Available: core, x402, attestation, verification, compliance, regulatory, governance, registry, ops, or all.

Regulatory coverage

EU AI Act (Articles 9–15, 17, 26, 49, 72, 73, Annexes IV/XI/XII), SR 11-7, OCC, FDIC, NIST AI RMF 1.0, TX TRAIGA, CO AI Act, HIPAA, EU DSA, NIS2, SEC, CFTC, ECOA Reg B, NYC LL144.

Tools (50+ across 9 modules)

• attest — attest an AI decision (local free, HCS with key)
• verify — verify attestation by ID
• get_proof — ZK Merkle inclusion proof
• register_agent — request free developer API key
• status — federation health
• framework_detect — auto-detect regulatory frameworks
• cost_estimate — monthly cost projection
• compliance_tag — attach framework tags (Standard+)
• bundle_query — query bundles (Standard+)

Architecture

• Post-quantum signatures: ML-DSA-65 (NIST FIPS 204) via liboqs
• Merkle aggregation: N-tier, SHA3-256, up to 1,000,000:1 compression
• Anchoring: Hedera mainnet HCS topic 0.0.10416909
• Federation: 5 geo-distributed nodes (US, SG, JP, CA, EU)
• ZK proofs: Noir beta.19, depth-20 Poseidon2 Merkle inclusion

Links

• Homepage: https://rubric-protocol.com
• Pricing: https://rubric-protocol.com/pricing
• Status: https://rubric-protocol.com/status
• Changelog: ./CHANGELOG.md