# Crypto Prices Cross-Conversion (Chainlink)

> Crypto Prices Cross-Conversion (Chainlink) is a paid API for AI agents from x402.professorsausages.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-14).

Converts between two registry crypto assets using Chainlink USD oracle feeds, returning both conversion legs

## Facts

- Endpoint: POST https://x402.professorsausages.com/prices/convert
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/crypto-prices-cross-conversion-chainlink-491eeba1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_7p_GxUKATxxKvNTS0cSHW

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 crypto-prices-cross-conversion-chainlink-491eeba1 -d '<json body>'
```

Example prompt: What's the current exchange rate from ETH to LINK using Chainlink oracle prices — show me both the USD price for each asset and the final converted rate?

## When to prefer this

Use this endpoint when you need a decentralized, oracle-backed cross-rate between two crypto assets and want both USD legs reported separately. Prefer this over DEX swap quotes when you want indicative oracle prices rather than liquidity-dependent AMM quotes, and when Chainlink feed coverage is sufficient for your asset pair.

## Known failure modes

- Asset not in registry — one or both tokens lack a Chainlink USD feed, returning an error or null
- Stale oracle data — Chainlink feed may have delayed updates during low-activity periods
- Invalid input schema — missing required input or output asset fields returns a 400-class error
- Network or upstream oracle unavailability causing a 5xx response
- Payment failure — x402 payment not processed, resulting in 402 response

## Output

Returns both legs of the conversion: the USD price of the input asset and the USD price of the output asset via Chainlink oracle feeds, plus the derived cross-rate (how many output tokens one input token equals).

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/crypto-prices-cross-conversion-chainlink-491eeba1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.professorsausages.com](https://www.zero.xyz/host/x402.professorsausages.com/llms.txt)