@insumermodel/mppx-token-gate

Add wallet auth to mppx routes using signed attestations. One API call checks token/NFT ownership across 30 EVM chains + Solana + XRPL + Bitcoin — no RPC management, no viem transports, no in-house balance checks.

How it works

mppx embeds the payer's identity in every payment credential as a DID string (credential.source: "did:pkh:eip155:8453:0xABC..."). tokenGate reads that address, calls InsumerAPI to check on-chain ownership, and short-circuits the payment flow for holders.

Request arrives with a payment credential
tokenGate extracts the payer address from credential.source
InsumerAPI checks ownership and returns an ECDSA P-256 signed result
Token holder → free receipt returned (reference: "token-gate🆓{attestationId}")
Non-holder → delegates to the original verify (normal payment proceeds)

The attestation signature is verifiable offline via JWKS — downstream services can independently verify the gate decision.

Install

npm install @insumermodel/mppx-token-gate

Usage

import { Mppx, tempo } from 'mppx/server'
import { tokenGate } from '@insumermodel/mppx-token-gate'

const tempoCharge = tempo({
  currency: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913',
  recipient: '0xYourAddress',
})

const gatedCharge = tokenGate(tempoCharge, {
  apiKey: process.env.INSUMER_API_KEY,
  conditions: [{
    type: 'nft_ownership',
    contractAddress: '0xYourNFT',
    chainId: 8453,        // Base
  }],
})

const mppx = Mppx.create({ methods: [gatedCharge] })

Works with any framework (Hono, Express, Elysia, Next.js) and any payment method (tempo, stripe) — it wraps Method.Server, so no middleware changes needed.

API key

Get a free key (instant, no signup):

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"}'

Or set INSUMER_API_KEY as an environment variable.

Options

Option	Type	Default	Description
`apiKey`	`string`	`env.INSUMER_API_KEY`	InsumerAPI key
`conditions`	`TokenCondition[]`	—	Token/NFT conditions to check
`matchMode`	`'any' \| 'all'`	`'any'`	Whether holder must satisfy any or all conditions
`cacheTtlSeconds`	`number`	`300`	In-memory ownership cache TTL
`jwt`	`boolean`	`false`	Request ES256 JWT alongside raw attestation
`apiBaseUrl`	`string`	`https://api.insumermodel.com`	API base URL override

TokenCondition

Field	Type	Description
`contractAddress`	`string`	Token/NFT contract address
`chainId`	`number \| 'solana' \| 'xrpl'`	Chain identifier
`type`	`'token_balance' \| 'nft_ownership'`	Condition type
`threshold`	`number`	Min balance (token_balance only, default 1)
`decimals`	`number`	Token decimals (auto-detected on most EVM chains)
`label`	`string`	Human-readable label
`currency`	`string`	XRPL currency code
`taxon`	`number`	XRPL NFT taxon filter

Supported chains

30 EVM chains (Ethereum, Base, Polygon, Arbitrum, Optimism, BNB, Avalanche, and 23 more) + Solana + XRPL + Bitcoin.

Full chain list

Distinguishing free vs paid access

const receipt = Receipt.fromResponse(response)
if (receipt.reference.startsWith('token-gate🆓')) {
  // Free access — attestation ID is in the reference
  const attestationId = receipt.reference.replace('token-gate🆓', '')
} else {
  // Paid access
}

Fail-open behavior

If the attestation API is unreachable, the wrapper falls through to the original payment method. Token holders pay normally; non-holders are unaffected.

License

MIT