Pyfile Toolkit: Provably-Fair Winner Selection

Use this endpoint when you need cryptographically verifiable, auditable random selection from a discrete set of named candidates — especially for giveaways, raffles, or contests where participants need proof the draw was not manipulated. Prefer this over a simple random number generator when auditability and a provable commit-reveal scheme matter. Use the companion commit endpoint first if you want to publish the server seed hash before drawing.

• Missing or empty candidates parameter returns an error
• Invalid or malformed candidates list may produce unexpected results
• Round ID or nonce mismatch prevents verification against a prior commit
• Payment failure (402) if x402 micropayment is not included or insufficient
• Network timeout if the endpoint is unreachable on the Tailscale network