SERP Rank Tracking API for AI Agents

FastAF’s SERP endpoint returns Google search results as JSON, so you can find the position of a domain for a keyword with one call at $0.003 via x402.

How it works

1. Call /x402/v1/serp with your keyword.
2. Find your domain in the organic results and record its position.
3. Repeat per keyword on your schedule.

Related endpoints: /x402/v1/news (Google News), /x402/v1/ai (Google AI answers, $0.01 per call) to see what Google’s AI says for a query.

Honest comparison

Dedicated rank trackers (dashboards, history, keyword volumes) do more out of the box. FastAF gives raw SERP JSON for agents and scripts. SerpAPI covers many more search engines; see the FastAF vs SerpApi comparison.

Pricing

Pricing: 500 free credits every month after email verification; x402 pay-per-call from $0.003; optional prepaid credit packs from $10 for 20,000 credits, without expiry.

Pricing source: FastAF OpenAPI, read October 27, 2026. Live payment challenges are authoritative.

How should an agent use search results?

Use a focused query, then inspect source pages for claims that matter. Search snippets help discover sources but are not substitutes for reading them.

What should you validate?

Check returned fields before using them in an agent decision. Missing fields are not evidence of zero values; preserve provenance and use bounded retries.

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