# x4o2

> Pay-per-call market and social trading data APIs for agents. Every /v1 route on every service answers an unpaid request with 402 Payment Required and x402 payment terms (USDC on Base, eip155:8453); pay with any x402 client and retry. No keys, no signup.

## Services

- [FOMO Data API](https://fomo.x4o2.com): FOMO (fomo.family) social trading data: token market panel, holders, theses, activity and trader profiles. 0.001 USDC per call via x402 on eip155:8453.
  - OpenAPI: https://fomo.x4o2.com/openapi.json
  - llms.txt: https://fomo.x4o2.com/llms.txt
  - Health: https://fomo.x4o2.com/health
- [pump.fun Data API](https://pump.x4o2.com): pump.fun market and social trading data: coin overview and stats, top holders with usernames and P&L, top traders, trade tape, candles, trending and live boards, search, the P&L leaderboard and trader profiles with portfolios. 0.001 USDC per call via x402 on eip155:8453.
  - OpenAPI: https://pump.x4o2.com/openapi.json
  - llms.txt: https://pump.x4o2.com/llms.txt
  - Health: https://pump.x4o2.com/health

## Free API key (testing)

Get a key with an email at https://x4o2.com/keys and send it as "Authorization: Bearer <key>". Free requests are served while the service has spare capacity; when busy you get 429 with Retry-After. Paid x402 requests always go through.

## How to pay

1. GET the route. The 402 response carries PAYMENT-REQUIRED terms (scheme exact, USDC on Base, the price, the payee).
2. Sign the payment with a Base wallet holding USDC (e.g. @x402/fetch with wrapFetchWithPayment) and retry with PAYMENT-SIGNATURE.
3. The 200 response carries PAYMENT-RESPONSE with the settlement receipt. Nothing is charged on 4xx/5xx.

## Index

- Machine-readable list: https://x4o2.com/index.json
- Status: https://x4o2.com/health
- Contact: contact@x4o2.com