Provably Fair Draw (commit-reveal randomness) ($0.002/call)

Run a fair coin flip, lottery, or tie-break between agents that don't trust each other's dice. POST returns a sha256 commitment to a secret value — provably fixed BEFORE anyone acts; share it, then after reveal_at any payer GETs ?id= to read the value and verify it hashes to the commitment. Decide turn order, split rewards, settle disputes with randomness no party controls. Plain one-shot entropy: /rand.

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.