{"uid":"cap_LwdDJYtep-yQ83UhEXc9-","slug":"proof-random-api-drand-beacon-evidence-endpoint-819252c5","name":"Proof Random API – drand Beacon Evidence Endpoint","description":"A free drand quicknet beacon relay with nonce-bound reproducible sampling. Client-side BLS verification required.","url":"https://proof-random-api.pn-26f.workers.dev/v1/evidence?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","required":["question"],"properties":{"sources":{"type":"array"},"question":{"type":"string"}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.15","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.15/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.15","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.15","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_dggMcEBYkkETi6hIx124P","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.15","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Relays a verifiable drand quicknet randomness beacon with nonce-bound reproducible sampling, returning cryptographic evidence for a given question","exampleAgentPrompt":"I need a cryptographically verifiable, nonce-bound random evidence sample from the drand quicknet beacon for the question 'which winner gets the prize in round 42 of our lottery?' — I'll verify the BLS proof on my end.","exampleUseCases":[{"title":"Provably fair lottery draw","prompt":"Run a verifiable randomness draw using the drand quicknet beacon for the question 'which of these 100 ticket holders wins the jackpot?' so I can BLS-verify the result myself."},{"title":"On-chain random seed for NFT mint","prompt":"I need a reproducible, nonce-bound random beacon sample for the question 'what are the trait values for NFT token #5001 in our drop?' so I can use it as a verifiable seed on-chain."},{"title":"Audit-grade random assignment","prompt":"Generate a cryptographic randomness evidence payload for the question 'which auditor is assigned to client XYZ for Q3?' using the drand quicknet relay so the selection is tamper-proof and verifiable."}],"resultDescription":"Returns a cryptographic evidence payload containing the drand quicknet beacon round data, a BLS-verifiable randomness value, and a nonce binding it to the submitted question. The client is expected to perform BLS signature verification independently to confirm authenticity.","failureModes":["Missing required 'question' field returns 400 Bad Request","drand network unavailability causes relay failure or timeout","Invalid sources array format may result in a 422 or ignored field","BLS verification failure on client side if beacon data is malformed","Payment not confirmed via x402 protocol results in 402 Payment Required"],"whenToPreferThis":"Choose this endpoint when you need publicly verifiable, tamper-resistant randomness backed by the drand quicknet beacon and you are able to perform client-side BLS verification. It is ideal for provably fair draws, on-chain random seeds, and audit-grade random assignments where trust-minimized, reproducible randomness is required. Prefer this over centralized RNG APIs when cryptographic verifiability and nonce-binding to a specific question are essential requirements.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-22T00:31:40.114Z","isFirstParty":false,"canonicalSlug":"proof-random-api-drand-beacon-evidence-endpoint-819252c5"}