@maximprotocol/sdk

The official TypeScript SDK for Maxim Protocol — unified payment infrastructure for AI agents.

One API. Any protocol (x402 + MPP). Every transaction on Solana.

Install

npm install @maximprotocol/sdk

Requires Node.js 18+.

Quick start

import { MaximProtocol } from "@maximprotocol/sdk";

const maxim = new MaximProtocol({
  agentId: "my-agent",
  apiKey: process.env.MAXIM_API_KEY!,
});

// Pay for a resource — protocol detected automatically
const result = await maxim.pay({
  endpoint: "https://api.service.com/resource",
  method: "POST",
  body: { query: "..." },
});

console.log(result.txHash);      // Solana transaction hash
console.log(result.amountPaid);  // { usdc: 0.002 }
console.log(result.protocol);   // "x402" | "mpp"
console.log(result.data);        // the actual API response

Wallet

// Get wallet address and balance
const wallet = await maxim.wallet.get();
console.log(wallet.address);         // 7xKXtg...mQfJL
console.log(wallet.balance.usdc);    // 42.50

// Just the balance
const { usdc } = await maxim.wallet.balance();

// Fund the wallet
await maxim.wallet.fund({ usdc: 50 });

Transactions

// List recent transactions
const { transactions, total } = await maxim.transactions.list({ limit: 50 });

// Filter by protocol or date range
const x402Only = await maxim.transactions.list({
  protocol: "x402",
  from: "2026-01-01T00:00:00Z",
  to: "2026-01-31T23:59:59Z",
});

// Get a single transaction
const tx = await maxim.transactions.get("5xKXtg...");
console.log(tx.solanaTxLink);

Spend policies

await maxim.policies.set({
  dailyBudget: { usdc: 100 },
  perCallLimit: { usdc: 1.00 },
  allowedDomains: ["api.dune.com", "api.browserbase.com", "fal.ai"],
  rateLimit: { calls: 500, window: "1h" },
});

const current = await maxim.policies.get();

ZK Privacy Mode

const result = await maxim.pay({
  endpoint: "https://api.service.com/resource",
  method: "POST",
  body: { query: "..." },
  privacy: {
    mode: "full",                           // "transparent" | "confidential_amount" | "full"
    disclosureKey: complianceOfficerPubKey, // optional — auditor can decrypt
  },
});

console.log(result.txHash);          // nullifier hash — no identity on-chain
console.log(result.privateNote);     // encrypted note for your records
console.log(result.disclosureProof); // openable only by disclosureKey holder

Error handling

import {
  MaximProtocol,
  InsufficientFundsError,
  PolicyViolationError,
  RateLimitError,
  AuthenticationError,
} from "@maximprotocol/sdk";

try {
  const result = await maxim.pay({ endpoint: "https://api.service.com/resource" });
} catch (err) {
  if (err instanceof InsufficientFundsError) {
    // top up the wallet
  } else if (err instanceof PolicyViolationError) {
    // payment blocked by spend policy
  } else if (err instanceof RateLimitError) {
    // slow down
  }
}

API reference

new MaximProtocol(config)

| Option | Type | Required | Description | |--------|------|----------|-------------| | agentId | string | Yes | Unique identifier for this agent | | apiKey | string | Yes | Your Maxim Protocol API key | | baseUrl | string | No | Override the API base URL (default: https://api.maximprotocol.com) |

maxim.pay(options)

Routes a payment through x402 or MPP — detected automatically.

| Option | Type | Default | Description | |--------|------|---------|-------------| | endpoint | string | — | The service URL to call | | method | string | "GET" | HTTP method | | body | unknown | — | Request body | | headers | Record<string, string> | — | Additional request headers | | privacy | PrivacyOptions | — | Enable ZK privacy mode | | idempotencyKey | string | — | Prevent duplicate payments |

Docs · Dashboard · maximprotocol.com