# Percall API

> Pay-per-request API platform with instant micropayment settlement via x402 v2 on Base Mainnet.

## Overview
Percall API provides pay-as-you-go APIs for autonomous AI agents and developers. Rather than requiring subscriptions or API keys, endpoints return HTTP 402 with an EIP-3009 payment challenge. Once signed by a funded wallet, endpoints return instant structured data.

- Homepage: https://percallapi.com/
- OpenAPI 3.1 Specification: https://percallapi.com/openapi.json
- Agentic Resource Discovery Manifest: https://percallapi.com/.well-known/ard.json
- Settlement Network: Base Mainnet (eip155:8453)
- Settlement Asset: USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913)
- Payment Protocol: x402 Version 2 (EIP-3009 transfer authorization)
- Receiving Address: 0xED6013a7f5A5cD54E21e5BDf8028a76A4E7b2ee5

## Available Endpoints

### 1. Domain WHOIS Lookup
- Endpoint: `https://percallapi.com/whois`
- Method: `GET`
- Price: `0.01 USDC` (10,000 base units)
- Access Mode: `per_request`
- Query Parameters:
  - `domain` (string, required): Domain name to query (e.g. `cloudflare.com`, `coinbase.com`).
- Response Format: `application/json`
- Unpaid Response: `HTTP 402 Payment Required` with x402 v2 challenge headers.
- Paid Response: `HTTP 200 OK` with full WHOIS records (domain_name, registrar, status, creation_date, expiration_date, name_servers).

### How AI Agents Invoke This API
1. Send initial GET request to `https://percallapi.com/whois?domain=example.com`.
2. Parse `HTTP 402` response containing price, USDC asset, and payment challenge parameters.
3. Sign EIP-3009 transfer authorization using agent's Base wallet.
4. Resubmit GET request with `payment-signature: <signed_payload>` header to retrieve data.