Crypto Fear & Greed Index ($0.002/call)

Crypto market sentiment: the Fear & Greed Index (0=extreme fear, 100=extreme greed) with classification, plus optional history. Query: days (1-90, default 7). Use as a contrarian signal, regime filter, or risk gauge in trading loops.

Paid endpoint: $0.002 per call via the x402 protocol (USDC on Base). An unpaid request returns 402 with payment requirements in the PAYMENT-REQUIRED response header; attach payment and retry.