mcp-server-insumer

MCP server for The Insumer Model — read-first blockchain verification infrastructure that returns ECDSA-signed, privacy-preserving booleans across 32 chains without exposing wallet balances or requiring trust in the API provider.

Enables AI agents (Claude Desktop, Cursor, Windsurf, and any MCP-compatible client) to autonomously verify on-chain conditions, discover merchants, generate signed discount codes, and onboard new merchants. Not a loyalty program. Not a reputation network. Not an identity system.

In production: DJD Agent Score (Coinbase x402 ecosystem) uses InsumerAPI for AI agent wallet trust scoring. Case study.

Also available as: LangChain (25 tools, PyPI) | langchain-community (25 tools, PR #549) | ElizaOS (3 actions, npm) | OpenAI GPT (GPT Store) | insumer-verify (client-side verification, npm)

Full AI Agent Verification API guide — covers all 32 chains, trust profiles, commerce protocols, and signature verification.

Quick Start

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "insumer": {
      "command": "npx",
      "args": ["-y", "mcp-server-insumer"],
      "env": {
        "INSUMER_API_KEY": "insr_live_..."
      }
    }
  }
}

Cursor / Windsurf

Add to your MCP settings:

{
  "insumer": {
    "command": "npx",
    "args": ["-y", "mcp-server-insumer"],
    "env": {
      "INSUMER_API_KEY": "insr_live_..."
    }
  }
}

Get an API Key

Option A — Let your agent do it: Start the server without a key. Your AI agent can call the insumer_setup tool with your email to generate a free key instantly. Add it to your config and restart.

Option B — Terminal (no browser needed):

curl -s -X POST https://us-central1-insumer-merchant.cloudfunctions.net/createDeveloperApiKey \
  -H "Content-Type: application/json" \
  -d '{"email": "[email protected]", "appName": "MCP Server", "tier": "free"}' | jq .

Returns an insr_live_... key with 10 credits and 100 calls/day. One free key per email.

Option C — Browser: Go to insumermodel.com/developers and generate a free key instantly.

Set it as INSUMER_API_KEY in your config.

What You Get Back

When your agent calls insumer_attest, you get an ECDSA-signed attestation:

{
  "ok": true,
  "data": {
    "attestation": {
      "id": "ATST-A7C3E",
      "pass": true,
      "results": [
        {
          "condition": 0,
          "met": true,
          "label": "USDC >= 1000 on Ethereum",
          "type": "token_balance",
          "chainId": 1,
          "evaluatedCondition": {
            "chainId": 1,
            "contractAddress": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
            "decimals": 6,
            "operator": "gte",
            "threshold": 1000,
            "type": "token_balance"
          },
          "conditionHash": "0x8a3b...",
          "blockNumber": "0x129e3f7",
          "blockTimestamp": "2026-02-28T12:34:56.000Z"
        }
      ],
      "passCount": 1,
      "failCount": 0,
      "attestedAt": "2026-02-28T12:34:57.000Z",
      "expiresAt": "2026-02-28T13:04:57.000Z"
    },
    "sig": "MEUCIQD...(base64 ECDSA signature)...",
    "kid": "insumer-attest-v1"
  },
  "meta": {
    "version": "1.0",
    "timestamp": "2026-02-28T12:34:57.000Z",
    "creditsCharged": 1,
    "creditsRemaining": 99
  }
}

The sig is an ECDSA P-256 signature over {id, pass, results, attestedAt}. The kid identifies which key signed it. The conditionHash is a SHA-256 of the exact condition logic that was evaluated.

No balances. No amounts. Just a cryptographically signed true/false.

For XRPL conditions, results include ledgerIndex, ledgerHash (validated ledger hash), and trustLineState: { frozen: boolean } instead of blockNumber/blockTimestamp. Native XRP conditions include ledgerIndex and ledgerHash but not trustLineState. Frozen trust lines cause met: false.

Wallet Auth (JWT)

Add format: "jwt" to the insumer_attest tool parameters to receive the attestation as a standard JWT bearer token:

{
  "wallet": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
  "conditions": [ ... ],
  "format": "jwt"
}

The response includes an additional jwt field containing an ES256-signed JWT. This token is verifiable by any standard JWT library via the JWKS endpoint at GET /v1/jwks — making it compatible with Kong, Nginx, Cloudflare Access, AWS API Gateway, and other middleware that accepts JWT bearer tokens.

Verify the Response

Your agent gets the attestation. Your application should verify it. Install insumer-verify:

npm install insumer-verify

import { verifyAttestation } from "insumer-verify";

// attestationResponse = the full API envelope {ok, data: {attestation, sig, kid}, meta}
// Do NOT pass attestationResponse.data — the function expects the outer envelope
const result = await verifyAttestation(attestationResponse, {
  jwksUrl: "https://insumermodel.com/.well-known/jwks.json",
  maxAge: 120, // reject if block data is older than 2 minutes
});

if (result.valid) {
  // Signature verified, condition hashes match, not expired
  const pass = attestationResponse.data.attestation.pass;
  console.log(`Attestation ${pass ? "passed" : "failed"} all conditions`);
} else {
  console.log("Verification failed:", result.checks);
}

This runs 4 independent checks: ECDSA signature, condition hash integrity, block freshness, and attestation expiry. Zero runtime dependencies, uses Web Crypto API.

Tools (26)

Setup (free, no auth)

| Tool | Description | |------|-------------| | insumer_setup | Generate a free API key instantly. Takes an email, returns an insr_live_... key with 10 credits. No credit card required. |

Key Discovery (free)

| Tool | Description | |------|-------------| | insumer_jwks | Get the JWKS containing InsumerAPI's ECDSA P-256 public signing key. Use the kid from attestation responses to match the correct key. |

On-Chain Verification (cost credits)

| Tool | Description | |------|-------------| | insumer_attest | Verify on-chain conditions (token balances, NFT ownership, EAS attestations, Farcaster identity). Returns ECDSA-signed boolean with kid, evaluatedCondition, conditionHash (SHA-256), and blockNumber/blockTimestamp. 1 credit. Optional proof: "merkle" for EIP-1186 Merkle storage proofs (2 credits). | | insumer_compliance_templates | List available EAS compliance templates (Coinbase Verifications on Base, Gitcoin Passport on Optimism). Free. | | insumer_wallet_trust | Generate ECDSA-signed wallet trust fact profile. 17 base checks (up to 20 with optional Solana + XRPL) across stablecoins, governance, NFTs, staking, and cross-chain positions. 3 credits (6 with merkle). | | insumer_batch_wallet_trust | Batch trust profiles for up to 10 wallets. Each wallet object supports optional solanaWallet and xrplWallet. Shared block fetches, 5-8x faster. Partial success supported. 3 credits/wallet (6 with merkle). | | insumer_verify | Create signed discount code (INSR-XXXXX, 30-min expiry) for a wallet at a merchant. 1 merchant credit. |

Discovery (free)

| Tool | Description | |------|-------------| | insumer_list_merchants | Browse the merchant directory. Filter by token, verification status. | | insumer_get_merchant | Get full public merchant profile. | | insumer_list_tokens | List all registered tokens and NFTs. Filter by chain, symbol, type. | | insumer_check_discount | Calculate discount for a wallet at a merchant. |

Credits

| Tool | Description | |------|-------------| | insumer_credits | Check credit balance and tier. | | insumer_buy_credits | Buy verification credits with USDC. Volume discounts: $0.04–$0.02/call. Supported chains: Ethereum, Base, Polygon, Arbitrum, Optimism, BNB Chain, Avalanche, Solana. Non-refundable. First purchase registers sender wallet; subsequent purchases must match or include updateWallet: true. | | insumer_confirm_payment | Confirm USDC payment for a discount code. |

Merchant Onboarding (owner-only)

| Tool | Description | |------|-------------| | insumer_create_merchant | Create new merchant. Receives 100 free credits. | | insumer_merchant_status | Get full private merchant details. | | insumer_configure_tokens | Set token discount tiers. | | insumer_configure_nfts | Set NFT collection discounts. | | insumer_configure_settings | Set discount mode, cap, USDC payments. | | insumer_publish_directory | Publish merchant to public directory. | | insumer_buy_merchant_credits | Buy merchant verification credits with USDC. Volume discounts: $0.04–$0.02/call. Owner only. Non-refundable. First purchase registers sender wallet; subsequent purchases must match or include updateWallet: true. |

Domain Verification (owner-only)

| Tool | Description | |------|-------------| | insumer_request_domain_verification | Request a verification token for a merchant's domain. Returns token and 3 methods (DNS TXT, meta tag, file upload). | | insumer_verify_domain | Complete domain verification after placing the token. Verified merchants get a trust badge. |

Commerce Protocol Integration

| Tool | Description | |------|-------------| | insumer_acp_discount | Check discount eligibility in OpenAI/Stripe ACP format. Returns coupon objects and per-item allocations. 1 merchant credit. | | insumer_ucp_discount | Check discount eligibility in Google UCP format. Returns title, extension field, and applied array. 1 merchant credit. | | insumer_validate_code | Validate an INSR-XXXXX discount code. Returns validity, discount percent, expiry. Free, no auth. |

Pricing

Tiers: Free (10 credits) | Pro $9/mo (10,000/day) | Enterprise $29/mo (100,000/day)

USDC volume discounts: $5–$99 = $0.04/call (25 credits/$1) · $100–$499 = $0.03 (33/$1, 25% off) · $500+ = $0.02 (50/$1, 50% off)

Platform wallets (USDC only):

• EVM: 0xAd982CB19aCCa2923Df8F687C0614a7700255a23
• Solana: 6a1mLjefhvSJX1sEX8PTnionbE9DqoYjU6F6bNkT4Ydr

Supported USDC chains: Ethereum, Base, Polygon, Arbitrum, Optimism, BNB Chain, Avalanche, Solana. USDC sent on unsupported chains cannot be recovered. All purchases are final and non-refundable. Full pricing →

Handling rpc_failure Errors

If the API cannot reach one or more data sources (RPC nodes, Helius, XRPL, Covalent) after retries, endpoints that produce signed attestations (insumer_attest, insumer_trust, insumer_trust_batch) return ok: false with error code rpc_failure. No signature, no JWT, no credits charged. This is a retryable error — the MCP client should retry after a short delay (2-5 seconds).

Important: rpc_failure is NOT a verification failure. Do not treat it as pass: false. It means the data source was temporarily unavailable and the API refused to sign an unverified result.

Supported Chains (32)

26 direct-RPC chains: Ethereum, BNB Chain, Base, Avalanche, Polygon, Arbitrum, Optimism, Chiliz, Soneium, Plume, World Chain, Sonic, Gnosis, Mantle, Scroll, Linea, ZKsync, Blast, Celo, Moonbeam, opBNB, Unichain, Ink, Sei, Berachain, ApeChain

4 Covalent chains: Taiko, Ronin, Moonriver, Viction

Non-EVM: Solana, XRPL (XRP Ledger — native XRP, trust line tokens, NFTs)

Development

npm install
npm run build

# Test with MCP Inspector
npx @modelcontextprotocol/inspector node build/index.js

License

MIT