Developer Guide

Get started integrating agent-payable APIs into your AI agent stack.

What is APPD?

APPD is a curated directory of APIs that AI agents can autonomously discover and pay for. Every listing is scored on uptime, latency, protocol compliance, pricing transparency, and documentation quality.

For AI Agents

Use the APPD API to discover payable services programmatically. Filter by protocol, category, pricing model, and more.

For Developers

Browse the directory to find agent-compatible APIs for your stack. Each listing includes scoring details and integration guides.

API Usage

The APPD API is free to use (100 requests/day). No authentication required.

Discover Services

// Discover all services
const res = await fetch('https://agentpay.directory/api/v1/services');
const { data, meta } = await res.json();

console.log(`Found ${meta.total} services`);
data.forEach(service => {
  console.log(`${service.name} — score: ${service.score}`);
});

Filter by Protocol

// Filter by protocol
const res = await fetch(
  'https://agentpay.directory/api/v1/services?protocol=x402&category=ai-models'
);
const { data } = await res.json();

// Find highest-scored x402 AI service
const best = data[0];
console.log(`Best: ${best.name} (${best.score}/100)`);

Integrate

// Integrate with an agent-payable API
const service = data[0];

const response = await fetch(service.endpoint, {
  headers: { 'Accept': 'application/json' },
});

if (response.status === 402) {
  // Handle payment flow based on protocol
  const payment = await response.json();
  // ... complete payment and retry
}