mcp-server-insumer

MCP server for InsumerAPI — condition-based access infrastructure. Send a wallet and conditions, get a signed boolean across 38 chains. No balances exposed, no identity required, no trust in the API provider needed.

Enables AI agents (Claude Desktop, Cursor, Windsurf, and any MCP-compatible client) to add condition-based access to any workflow — verify on-chain conditions, discover merchants, generate signed discount codes, and onboard new merchants.

In production: AsterPay — a regulated payments stack — runs live ERC-8183 agentic-commerce trust scoring on InsumerAPI. Case study.

Also available as: LangChain (26 tools, PyPI) | langchain-community (26 tools, PR #549) | ElizaOS (10 actions, npm) | OpenAI GPT (GPT Store) | insumer-verify (client-side verification, npm)

Full AI Agent Verification API guide — covers all 38 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 a key — no signup, no dashboard, no password

Three paths, all give you a working insr_live_... key in seconds with 100 reads/day and 10 verification credits. One free key per email.

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:

curl -s -X POST https://api.insumermodel.com/v1/keys/create \
  -H "Content-Type: application/json" \
  -d '{"email": "you@example.com", "appName": "MCP Server", "tier": "free"}'

Option C — Browser: Enter your email on insumermodel.com — the key appears inline.

Set it as INSUMER_API_KEY in your config.

Already have a key? Manage usage, top up, or upgrade at insumermodel.com/developers/account/.

Option D — Pay per call with x402 (no key at all)

Instead of a key, set INSUMER_PAYMENT_KEY to a throwaway Base wallet funded with a few dollars of USDC. Metered calls (insumer_attest, insumer_wallet_trust, insumer_batch_wallet_trust) are then paid inline via x402 — the server requests a price, signs an EIP-3009 USDC authorization on Base, and retries. No signup, no credits, no dashboard.

{
  "mcpServers": {
    "insumer": {
      "command": "npx",
      "args": ["-y", "mcp-server-insumer"],
      "env": { "INSUMER_PAYMENT_KEY": "0x<throwaway-wallet-private-key>" }
    }
  }
}

• Base USDC only; the wallet needs USDC but no ETH (settlement is gasless).
• Each call spends a few cents (attest $0.05, trust $0.15). Use a dedicated throwaway wallet funded with a small amount — never a wallet holding meaningful funds.
• If both INSUMER_API_KEY and INSUMER_PAYMENT_KEY are set, the key (credits) is used.

What You Get Back

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

{
  "ok": true,
  "data": {
    "attestation": {
      "id": "ATST-A7C3E1B2D4F56789",
      "pass": true,
      "results": [
        {
          "condition": 0,
          "met": true,
          "label": "USDC >= 1000 on Ethereum",
          "type": "token_balance",
          "chainId": 1,
          "evaluatedCondition": {
            "chainId": 1,
            "contractAddress": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
            "operator": "gte",
            "threshold": "1000",
            "type": "token_balance"
          },
          "conditionHash": "0x8a3b...",
          "blockNumber": "0x1799043",
          "blockTimestamp": "2026-03-26T20:04:23.000Z"
        }
      ],
      "passCount": 1,
      "failCount": 0,
      "attestedAt": "2026-02-28T12:34:57.000Z",
      "expiresAt": "2026-02-28T13:04:57.000Z"
    },
    "sig": "NgA7BO8SAildiTrgIQY2UyXsBrySZknkP85pT2Zqv8Hq0KsCsB8DRFVMkXgnXtCXrbb726Is6k4LyyBYU+f/Pw==",
    "kid": "insumer-attest-v2",
    "pqSig": "<base64 ML-DSA-65 signature>",
    "pqKid": "insumer-attest-pq1"
  },
  "meta": {
    "version": "1.0",
    "timestamp": "2026-02-28T12:34:57.000Z",
    "creditsRemaining": 99,
    "creditsCharged": 1
  }
}

The sig is an ECDSA P-256 signature (base64, P1363 r||s, 88 characters). The kid identifies the key and selects the signed bytes: insumer-attest-v2 signs "insumer.attestation.v2\n" + canonical_json({v: 2, id, pass, results, attestedAt}) (keys sorted at every level); insumer-attest-v1 signs the bare JSON.stringify of {id, pass, results, attestedAt} in insertion order. Since 2026-09-01 every attest and trust response also carries a post-quantum companion, pqSig and pqKid (ML-DSA-65 over the post-quantum domain tag plus the same classical preimage the kid selects), added beside sig and kid without changing them. 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, and beside it a pqJwt sibling (a compact JWS with alg ML-DSA-65 carrying the same claims, signed under insumer-attest-pq1). The jwt 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, pqSig, pqKid}, 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 reports five independent verdicts: ECDSA signature, condition hash integrity, block freshness, attestation expiry, and the post-quantum companion (insumer-verify 1.8.1+ reports it as verified, refuted, absent, or unverifiable). Zero runtime dependencies, uses Web Crypto API.

Tools (27)

Setup (free, no auth)

Key Discovery (free)

On-Chain Verification (cost credits)

token_balance thresholds are decimal strings. Pass threshold as "100", not 100. Keys created from 2026-06-10 sign with kid: insumer-attest-v2, which preserves full precision and rejects a JSON number with a 400. The insumer_attest tool accepts a number or string and coerces to the canonical string; older insumer-attest-v1 keys accept either.