API use cases for AI agents

How do you make a real request?

This example calls Google SERP API using its documented input. Save the API key from the signup email, confirm your email and set FASTAF_API_KEY in your server environment.

curl --fail-with-body -H "Authorization: Bearer $FASTAF_API_KEY" 'https://api.fastaf.co/v1/serp?query=best+espresso+machine+for+home&country=us&language=en'

# pip install fastaf-sdk
import os
from fastaf import FastAF

with FastAF(os.environ["FASTAF_API_KEY"]) as client:
    data = client.request("serp", {"query":"best espresso machine for home","country":"us","language":"en"})
    print(data)

Google SERP JSON. organic_results contains ranked title, link and snippet fields; search_information describes the query. Other Google result blocks may also appear.

The example costs 5 credits after the trial. Alternatively, this endpoint costs $0.003 per successful x402 call at the default configuration; FastAF x402 calls start at $0.003. These are separate billing modes.

For x402, request the same parameters under /x402/v1/serp without an API key, validate the live PAYMENT-REQUIRED challenge, then sign and retry with a payment-aware client. A bare curl request returns HTTP 402 and does not pay; unsupported higher-cost options require API-key billing.

Frequently asked questions