Utilities · x402

Verifiable Random pick — string selection with or without replacement bound to a future…

Verifiable Random pick — string selection with or without replacement bound to a future drand round the server waits for (typically 3-6s) and verifies locally, with a reproducible proof transcript.

by verifiable-random.use.x402atlas.com · discovered, not yet claimed by its owner · updated 2026-10-08

Mirrored from Coinbase's public x402 Bazaar. The description is the provider's own text and has not been reviewed here; the payment requirements are copied as published.

What it does

Verifiable Random pick — string selection with or without replacement bound to a future drand round the server waits for (typically 3-6s) and verifies locally, with a reproducible proof transcript.

Tags: verifiable-random · random-pick · random-selection · sample · drand · bazaar

Use with an agent

Discover. Agents find this listing with GET https://bazaar.saylorinnovations.com/discovery/search?query=…, the MCP tool search_resources, or /discovery/resources.
Inspect. Fetch /resources/28613.json for the price and payment options.
Pay. Call GET https://verifiable-random.use.x402atlas.com/pick. The provider answers 402 with its payment requirements. An x402 client signs one of the options below and retries with PAYMENT-SIGNATURE.
Execute. The provider returns 200 with the data. Agent Bazaar is not in the request path and never sees your payment.

For humans

You don't need an account or an API key; you need a wallet holding a small amount of USDC on Base, Polygon, Arbitrum One, Solana, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price: $0.005 / request
Protocol: x402 v2
Auth: No account or API key. Pay per request.
Networks: Base, Polygon, Arbitrum One, Solana
Calls (30d): 5 · 4 unique payers (third-party data from the public x402 Bazaar)

x402 payment requirements

Scheme	Network	Asset	Amount	Pay to	Timeout
exact	Base eip155:8453	USDC	$0.005	0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2	300s
exact	Polygon eip155:137	USDC	$0.005	0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2	300s
exact	Arbitrum One eip155:42161	USDC	$0.005	0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2	300s
exact	Solana solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp	USDC	$0.005	ASt6xvRyQ7ntERsmcYVMdLqZvz1GEN8Fzexzq62tXrNQ	300s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "5000",
    "amountUsd": 0.005,
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:137",
    "payTo": "0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2",
    "asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
    "amount": "5000",
    "amountUsd": 0.005,
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:42161",
    "payTo": "0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2",
    "asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
    "amount": "5000",
    "amountUsd": 0.005,
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "payTo": "ASt6xvRyQ7ntERsmcYVMdLqZvz1GEN8Fzexzq62tXrNQ",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "amount": "5000",
    "amountUsd": 0.005,
    "maxTimeoutSeconds": 300
  }
]

Schemas

Output schema (JSON Schema)

{
  "properties": {
    "example": {
      "additionalProperties": false,
      "description": "Verifiable Random result and complete drand derivation transcript.",
      "properties": {
        "algorithm_version": {
          "description": "Pinned canonicalization, derivation, and sampling algorithm version required to reproduce the result.",
          "enum": [
            "drand-hkdf-sha256-v1"
          ],
          "type": "string"
        },
        "beacon": {
          "additionalProperties": false,
          "description": "Locally verified drand Quicknet proof used as the public randomness source.",
          "properties": {
            "chain_hash": {
              "description": "Pinned Quicknet chain hash used to fetch and verify the round.",
              "enum": [
                "52db9ba70e0cc0f6eaf7803dd07447a1f5477735fd3f661792ba94600c84e971"
              ],
              "type": "string"
            },
            "network": {
              "description": "Pinned drand network name.",
              "enum": [
                "quicknet"
              ],
              "type": "string"
            },
            "randomness": {
              "description": "Lowercase hexadecimal randomness derived from the verified signature.",
              "pattern": "^[0-9a-f]{64}$",
              "type": "string"
            },
            "round": {
              "description": "Exact verified Quicknet round used for this result.",
              "minimum": 1,
              "type": "integer"
            },
            "scheduled_time": {
              "description": "Scheduled UTC publication time of the selected round.",
              "format": "date-time",
              "type": "string"
            },
            "scheme": {
              "description": "Pinned drand signature scheme.",
              "enum": [
                "bls-unchained-g1-rfc9380"
              ],
              "type": "string"
            },
            "signature": {
              "description": "Lowercase hexadecimal BLS signature verified against the pinned Quicknet public key.",
              "pattern": "^[0-9a-f]{96}$",
              "type": "string"
            }
          },
          "required": [
            "network",
            "chain_hash",
            "scheme",
            "round",
            "scheduled_time",
            "randomness",
            "signature"
          ],
          "type": "object"
        },
        "example_only": {
          "description": "True only in compiled catalog/keepalive examples; live paid results are false.",
          "type": "boolean"
        },
        "operation": {
          "description": "Random operation performed by this route.",
          "enum": [
            "pick"
          ],
          "type": "string"
        },
        "processed_at": {
          "description": "UTC time when the service accepted the request and committed to the round-selection decision.",
          "format": "date-time",
          "type": "string"
        },
        "request_hash": {
          "description": "Lowercase SHA-256 of your canonical request JSON — retain the exact request body so you can re-derive the result offline.",
          "pattern": "^[0-9a-f]{64}$",
          "type": "string"
        },
        "result": {
          "additionalProperties": false,
          "description": "Operation-specific result derived deterministically from the verified beacon and request hash.",
          "properties": {
            "items": {
              "description": "Selected strings in draw order.",
              "items": {
                "type": "string"
              },
              "type": "array"
            },
            "original_indices": {
              "description": "For each selected value, its zero-based position in the input array.",
              "items": {
                "type": "integer"
              },
              "type": "array"
            }
          },
          "required": [
            "items",
            "original_indices"
          ],
          "type": "object"
        },
        "selection_mode": {
          "description": "server_next means the server chose the next safe unpublished round, so you trust its selection chronology; client_fixed means the round is the one you committed to before paying and no other round can be substituted; example_only appears only in catalog examples.",
          "enum": [
            "server_next",
            "client_fixed",
            "example_only"
          ],
          "type": "string"
        },
        "target_round": {
          "description": "Echoes the round actually selected for this result; in server_next mode this is the server-chosen round, not the 0 you sent.",
          "minimum": 1,
          "type": "integer"
        }
      },
      "required": [
        "operation",
        "algorithm_version",
        "selection_mode",
        "target_round",
        "example_only",
        "processed_at",
        "request_hash",
        "beacon",
        "result"
      ],
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}

Example shape — generated from the schema, not a captured live response

{
  "example": {
    "algorithm_version": "drand-hkdf-sha256-v1",
    "beacon": {
      "chain_hash": "52db9ba70e0cc0f6eaf7803dd07447a1f5477735fd3f661792ba94600c84e971",
      "network": "quicknet",
      "randomness": "string",
      "round": 0,
      "scheduled_time": "2026-01-01T00:00:00Z",
      "scheme": "bls-unchained-g1-rfc9380",
      "signature": "string"
    },
    "example_only": true,
    "operation": "pick",
    "processed_at": "2026-01-01T00:00:00Z",
    "request_hash": "string",
    "result": {
      "items": [
        "string"
      ],
      "original_indices": [
        0
      ]
    },
    "selection_mode": "server_next",
    "target_round": 0
  },
  "type": "string"
}

Examples

curl

curl "https://verifiable-random.use.x402atlas.com/pick"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

JavaScript

const res = await fetch("https://verifiable-random.use.x402atlas.com/pick");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}

Python

import httpx
res = httpx.get("https://verifiable-random.use.x402atlas.com/pick")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header

Details

Provider: verifiable-random.use.x402atlas.com
Endpoint: https://verifiable-random.use.x402atlas.com/pick
Machine-readable: /resources/28613.json