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FairSeal VDF Random Number Generator
x402
FairSeal VDF Random Number Generator is a paid API for AI agents from x402.fairseal.io, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).
Returns a cryptographically verifiable random number backed by a Wesolowski 2048-bit Verifiable Delay Function (VDF), served from a pool for sub-2ms latency.
Price / call$0.005
Success—
StatusUnknown
How this service works
Verifiable random numbers with cryptographic epoch references. Wesolowski 2048-bit VDF epoch chain with on-chain MerkleAnchor reference. For unbiased randomness: POST /v1/rng/commit (free), then GET the reveal_url returned in the response. Do not construct reveal paths yourself.
Output
A cryptographically verifiable random number accompanied by a Wesolowski VDF proof (2048-bit), confirming the entropy was generated through a verifiable delay function and cannot be predicted or manipulated retroactively.
Example use cases
Provably fair on-chain lottery draw
“I need a tamper-proof random number for my on-chain lottery draw — something with a cryptographic proof so participants can verify the result was fair.”
Unbiased random seed for card shuffle
“Generate a verifiably unbiased random seed I can use to shuffle a deck of cards in my game, where players need to trust the randomness wasn't rigged.”
Random selection for NFT trait assignment
“I need a provably fair random number to assign traits to an NFT during mint — fetch me one with a verifiable proof so no one can claim I picked favorable traits.”
Technical details
Endpoint
GEThttps://x402.fairseal.io/v1/rng/latestWhen to prefer
Choose this endpoint when you need randomness that is publicly auditable and cryptographically verifiable — especially for lotteries, games, NFT mints, or smart contracts where trust in the RNG is critical. The VDF proof distinguishes it from standard PRNGs or simple HTTPS-served random numbers that lack auditability. Prefer it over raw OS/library entropy when stakeholders must be able to independently verify fairness post-hoc.
Side effects
- Pool unavailability causes delayed or missing response
- Payment of 0.001 USDC not received results in 402 Payment Required
- Rate limiting or pool exhaustion may cause transient errors
- Malformed or missing x402 payment header results in authentication failure
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object |
Tags
x402
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