# fly.ai Pay-Per-Request Market API

> fly.ai Pay-Per-Request Market API is a paid API for AI agents from flyai-x402.fly.dev, paid per call via x402, $0.05/call, status unknown (last checked 2026-10-12).

Accepts a POST request to a specific market reference endpoint and returns a single AI-generated answer, billed at $0.05 USDC per call via x402 micropayment protocol.

## Facts

- Endpoint: POST https://flyai-x402.fly.dev/market/%7Bref%7D?utm_source=zero.xyz
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fly-ai-pay-per-request-market-api-7b468653
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_pVpWzx66fzI1j3vxqc26I

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability fly-ai-pay-per-request-market-api-7b468653 -d '<json body>'
```

Example prompt: Ask fly.ai's market endpoint for ref 'weather-summary' what the typical climate is like in Lisbon in October — this is a pay-per-request call so it will charge $0.05 USDC via x402.

## When to prefer this

Choose this endpoint when you need a single, on-demand AI-generated answer billed per request via x402 micropayments in USDC, without a subscription or API key — ideal for agents that want pay-as-you-go AI access with crypto-native billing and no upfront commitment.

## Known failure modes

- 402 Payment Required if x402 payment header is missing or invalid
- Invalid or unknown market reference {ref} resulting in 404 Not Found
- Malformed request body causing 400 Bad Request
- Payment processing failure or insufficient USDC balance
- Timeout if the AI model takes too long to generate the answer
- Rate limiting if too many requests are submitted in a short window

## How this service works

Single answers, each paid on its own over x402. Guide: https://www.flyaiworld.com/x402-api.md

## Output

A single AI-generated text answer corresponding to the submitted query for the given market reference, returned after successful x402 micropayment processing at $0.05 USDC per call.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fly-ai-pay-per-request-market-api-7b468653/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from flyai-x402.fly.dev](https://www.zero.xyz/host/flyai-x402.fly.dev/llms.txt)