@delegare/sdk

The official TypeScript SDK for Delegare – Trustless payment delegation for AI agents.

Delegare empowers AI agents to spend money on behalf of users across the web without requiring a human-in-the-loop or a wallet popup for every transaction.

This SDK allows developers to:

1. Merchants: Accept programmatic AP2 Intent Mandates (SD-JWT-VC) as payment from agents.
2. Agents: Seamlessly satisfy x402 Payment Required paywalls using a pre-authorized budget.

Installation

npm install @delegare/sdk
# or
pnpm add @delegare/sdk
# or
yarn add @delegare/sdk

1. Agent Autonomy: x402 Auto-Payments

When building an AI agent, you often need to fetch data or invoke tools from monetized APIs (e.g., APIs protected by the x402 protocol or Google's Agentic Commerce Protocol).

Instead of halting the agent to prompt the user for payment, the Delegare SDK provides a drop-in replacement for the native fetch function. If the server returns a 402 Payment Required challenge, Delegare automatically signs an EIP-3009 authorization under the hood using the user's spending mandate, and retries the request seamlessly.

import { Delegare } from '@delegare/sdk';

// Initialize the client
const delegare = new Delegare({
  merchantId: 'm_your_agent_platform_id',
  apiKey: process.env.DELEGARE_API_KEY
});

// The user's pre-authorized spending token (SD-JWT-VC)
const intentMandate = "eyJhbGciOiJIUzI1Ni... (truncated)";

// 1. Fetch a resource that might be paywalled
// If the server returns 402, Delegare intercepts it, checks the required price 
// against the user's monthly budget, signs the payment, and fetches the data.
const response = await delegare.fetch(
  'https://api.premium-data-provider.com/weather',
  { method: 'GET' },
  intentMandate // Automatically authorize if x402 paywall is hit
);

const data = await response.json();
console.log(data); // Returns the premium data!

2. Merchants: Accept AP2 Intent Mandates

If you are a merchant, store, or service provider, you can use the SDK to charge an AI agent that visits your platform with a valid spending mandate.

import { Delegare } from '@delegare/sdk';

const delegare = new Delegare({
  merchantId: process.env.DELEGARE_MERCHANT_ID,
  apiKey: process.env.DELEGARE_API_KEY
});

// An AI agent sends you their intentMandate to buy something
app.post('/api/checkout', async (req, res) => {
  const { intentMandate, orderId } = req.body;

  try {
    const receipt = await delegare.charge({
      intentMandate,
      amountCents: 1500, // $15.00
      currency: 'usd',
      description: 'Premium AI API Call',
      idempotencyKey: orderId // Prevents double-charging
    });

    if (receipt.status === 'completed') {
      res.json({ success: true, orderId });
    } else {
      res.status(402).json({ error: 'Payment failed (limit exceeded or declined)' });
    }
  } catch (error) {
    res.status(400).json({ error: error.message });
  }
});

Core API Reference

delegare.fetch(url, init?, intentMandate?)

A wrapper around the native fetch API. If a 402 response is returned with X-PAYMENT requirements, it signs the payment securely and retries the request.

delegare.charge(params)

Execute a payment against a given AP2 intent mandate.

delegare.getBalance(intentMandate)

Query the remaining monthly limit for a specific mandate.

const balance = await delegare.getBalance('mandate_id_here');
console.log(`Remaining monthly budget: $${balance.remainingMonthlyBudgetCents / 100}`);

delegare.createSetupSession(params)

Generates a URL where your human users can safely authorize a spending budget for their agents.

const session = await delegare.createSetupSession({
  maxPerTxCents: 5000,          // $50 max per transaction
  maxMonthlySpendCents: 20000,  // $200 max per month
  rail: 'both'                  // Support fiat (Stripe) and crypto (Base USDC)
});
console.log(`Direct user to: ${session.setupUrl}`);

delegare.waitForSetup(sessionToken)

Polls the setup session until the user completes the flow in their browser, returning the newly minted intentMandate to be given to the agent.

const intentMandate = await delegare.waitForSetup(session.sessionToken);

Environments

By default, the SDK points to the Delegare production API. For testing, supply the sandbox baseUrl during initialization:

const delegare = new Delegare({
  merchantId: 'm_test_...',
  apiKey: 'dk_test_...',
  baseUrl: 'https://api.sandbox.delegare.dev/v1'
});

Links

• Documentation
• Dashboard
• GitHub