Wallet Auth reads what a wallet holds across 37 blockchains and returns a signed attestation. Boolean result, ECDSA-signed, no balance exposed.
Read on-chain conditions without running blockchain infrastructure or exposing wallet balances.
Supports 37 chains through a unified condition format: 31 EVM chains plus Solana, XRPL, Bitcoin, Tron, Stellar and Sui.
Free tier: 100 requests a day, 10 verification credits. One key per email, no credit card. Agents on EVM: pay with USDC and skip the email (see the wallet-paid path below).
Or via curl:
curl -X POST https://api.insumermodel.com/v1/keys/create \ -H "Content-Type: application/json" \ -d '{ "email": "you@example.com", "appName": "My App", "tier": "free" }'
{
"success": true,
"key": "insr_live_a1b2c3d4e5f6a1b2c3d4e5f6a1b2c3d4e5f6a1b2",
"name": "My App",
"tier": "free",
"dailyLimit": 100,
"apiKeyCredits": 10
}
Save the key value. It is shown once and cannot be retrieved later.
Send 5+ USDC on Base to 0xee432065474D2C852700f74e3fD81e2Bcc16a3D4, sign the payment with the same wallet, then POST the transaction hash and the signature. No email. The sender wallet becomes the key's identity, and an Insumer Access pass is minted to the same wallet so it can authenticate via wallet signature (see Wallet Auth below).
curl -X POST https://api.insumermodel.com/v1/keys/buy \ -H "Content-Type: application/json" \ -d '{ "txHash": "0x...", "chainId": 8453, "amount": 5, "appName": "my-agent", "senderSignature": "0x..." }'
senderSignature proves you control the wallet that paid: that wallet signs this exact text with personal_sign (five lines joined by \n, no trailing newline; the transaction hash in lowercase). Send the request without it and the 400 response carries the exact text to sign.
api.insumermodel.com Confirm the wallet that sent this payment. Purpose: key purchase Chain: eip155:8453 Transaction: 0x<lowercase tx hash>
Volume rates: $5–$99 = 25 credits/$1, $100–$499 = 33 credits/$1, $500+ = 50 credits/$1. USDC only, on Ethereum, Base, Polygon, Arbitrum, Optimism, BNB Chain, Avalanche or Solana (Solana wallets sign with signMessage and use Chain: solana). Non-EVM senders use X-API-Key auth; the Insumer Access pass mint happens on EVM purchases only.
Check if a wallet holds at least 1 USDC on Base. POST /v1/attest
Costs 1 credit ($0.04).
curl -X POST https://api.insumermodel.com/v1/attest \ -H "Content-Type: application/json" \ -H "X-API-Key: YOUR_API_KEY" \ -d '{ "wallet": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045", "conditions": [{ "type": "token_balance", "contractAddress": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913", "chainId": 8453, "threshold": "1", "label": "USDC >= 1" }] }' # wallet: vitalik.eth # contractAddress: USDC on Base (chainId 8453, 6 decimals)
Agents on EVM who bought their key via /v1/keys/buy can replace X-API-Key with Authorization: Wallet <envelope> instead. The envelope is base64 JSON containing a SIWE message scoped to api.insumermodel.com plus an EIP-191 signature. Drop-in middleware that handles the construction: @skyemeta/access on npm.
{
"ok": true,
"data": {
"attestation": {
"id": "ATST-E365DB7F2A9C0481",
"pass": true,
"results": [
{
"condition": 0,
"label": "USDC >= 1",
"type": "token_balance",
"chainId": 8453,
"met": true,
"evaluatedCondition": {
"type": "token_balance",
"chainId": 8453,
"contractAddress": "0x8335...2913",
"operator": "gte",
"threshold": "1"
},
"conditionHash": "0x448ddd3e...",
"blockNumber": "0x1772dde",
"blockTimestamp": "2026-03-06T12:00:00.000Z"
}
],
"passCount": 1,
"failCount": 0,
"attestedAt": "2026-03-06T12:00:01.000Z",
"expiresAt": "2026-03-06T12:30:01.000Z"
},
"sig": "rHObYHqV...",
"kid": "insumer-attest-v2",
"pqSig": "...",
"pqKid": "insumer-attest-pq1"
},
"meta": {
"creditsRemaining": 9,
"creditsCharged": 1,
"version": "1.0",
"timestamp": "2026-03-06T12:00:01.000Z"
}
}
pass: true: wallet meets all conditions
pass: false: one or more conditions failed
sig: ECDSA P-256 signature over the preimage the kid selects (v2: the domain tag plus canonical JSON of {v:2, id, pass, results, attestedAt}; v1: the bare JSON of those four fields), verify offline with insumer-verify
kid: identifies the signing key; fetch the public key from /.well-known/jwks.json
pqSig / pqKid: post-quantum signature (ML-DSA-65) beside sig, resolved from the same JWKS by pqKid; insumer-verify 1.8.1 and later reports it as a separate verdict. Verify all of it with insumer-verify, on npm or PyPI.
Attestations expire after 30 minutes (expiresAt) to prevent replay. The JWKS endpoint is cacheable (24h max-age); keys rotate rarely.
Copy-paste this into a file, set your API key, and run it. Makes the attestation request and verifies the signature in one script.
// npm install insumer-verify axios import axios from "axios"; import { verifyAttestation } from "insumer-verify"; const res = await axios.post( "https://api.insumermodel.com/v1/attest", { wallet: "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045", conditions: [{ type: "token_balance", contractAddress: "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913", chainId: 8453, threshold: "1" // decimal string (v2 keys reject a JSON number with 400) }] }, { headers: { "X-API-Key": process.env.INSUMER_API_KEY } } ); const verified = await verifyAttestation(res.data, { jwksUrl: "https://insumermodel.com/.well-known/jwks.json" }); console.log("Valid:", verified.valid); // true
Minimal example for your README:
const res = await axios.post( "https://api.insumermodel.com/v1/attest", { wallet: "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045", conditions: [{ type: "token_balance", contractAddress: "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913", chainId: 8453, threshold: "1" // decimal string (v2 keys reject a JSON number with 400) }] }, { headers: { "X-API-Key": process.env.INSUMER_API_KEY } } ); console.log(res.data.data.attestation.pass);
The insumer-verify npm package checks the ECDSA signature, condition hashes, expiry, pass/fail consistency, and the post-quantum signature in one call.
// npm install insumer-verify import { verifyAttestation } from "insumer-verify"; // Pass the full API response envelope, not response.data const response = await res.json(); const result = await verifyAttestation(response, { jwksUrl: "https://insumermodel.com/.well-known/jwks.json" }); console.log(result.valid); // true