Utilities · x402

Pick k of your items with or without replacement, optionally weighted by integer weight…

Pick k of your items with or without replacement, optionally weighted by integer weights (raffles, lotteries, sortition, A/B splits). One verified randomness draw, cumulative-weight search over a rejection-sampled uniform value, up to 10000 items. The exact r…

by animica.dev · discovered, not yet claimed by its owner · updated 2026-08-20

Not responding. This endpoint did not answer its last liveness check (2026-10-13). It may be temporarily down.

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

Tags: animica · bazaar · discovery

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/7536.json for the price and payment options.
Pay. Call GET https://animica.dev/x402/random/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, animica:1, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price: $0.00541 / request
Protocol: x402 v2
Auth: No account or API key. Pay per request.
Networks: Base, animica:1
Uptime: 0 of the last 1 checks answered
Calls (30d): 2 · 1 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	$0.00541	0x5D17c40FD6b119dc6006C4Ab3C20a917FCaB2aCD	60s
exact	animica:1 animica:1	ANM	52626799844	anim1zqpsmegc0qcvzjfukm89xs0zeu3eqyyyel7kelehuszvwfarqypky2gr946ga	60s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x5D17c40FD6b119dc6006C4Ab3C20a917FCaB2aCD",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "5410",
    "amountUsd": 0.00541,
    "maxTimeoutSeconds": 60
  },
  {
    "scheme": "exact",
    "network": "animica:1",
    "payTo": "anim1zqpsmegc0qcvzjfukm89xs0zeu3eqyyyel7kelehuszvwfarqypky2gr946ga",
    "asset": "ANM",
    "amount": "52626799844",
    "maxTimeoutSeconds": 60
  }
]

Schemas

Output schema (JSON Schema)

{
  "animica": {
    "catalog": "https://animica.dev/.well-known/x402",
    "content_type": "application/json",
    "currency": "USDC",
    "description": "Pick k of your items with or without replacement, optionally weighted by integer weights (raffles, lotteries, sortition, A/B splits). One verified randomness draw, cumulative-weight search over a rejection-sampled uniform value, up to 10000 items. The exact rule and the raw draw ride along so you can recompute the winners.",
    "documentation": "https://animica.dev/x402#product-random_pick",
    "free_trial": {
      "endpoint": "POST /x402/random/pick/trial",
      "limit_per_day": 3,
      "note": "Same code and same response shape as the paid endpoint. No payment, no payment headers. Quota is per client per UTC day; when it is spent this endpoint says so and points back here.",
      "price": "0",
      "url": "https://animica.dev/x402/random/pick/trial"
    },
    "name": "Weighted random pick",
    "openapi": "https://animica.dev/x402/openapi.json",
    "price": "0.005410",
    "product": "random_pick",
    "provider": "Animica",
    "terms": {
      "amount_atomic": "5410",
      "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "chain_id": 8453,
      "network": "eip155:8453",
      "pay_to": "0x5D17c40FD6b119dc6006C4Ab3C20a917FCaB2aCD",
      "scheme": "exact"
    },
    "x402_version": 2
  },
  "bazaar": {
    "discoverable": true,
    "info": {
      "input": {
        "body": {
          "items": [
            "a",
            "b",
            "c"
          ]
        },
        "bodyType": "json",
        "method": "POST",
        "type": "http"
      },
      "output": {
        "type": "json"
      }
    },
    "schema": {
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "properties": {
        "input": {
          "properties": {
            "body": {
              "properties": {
                "indices_only": {
                  "description": "omit the picked items and return only their 0-based indices — use it when the items are large: the response cap is 4000000 bytes and with replace:true the same item can be emitted k times",
                  "type": "boolean"
                },
                "items": {
                  "description": "candidates, 1..10000 entries (any JSON values)",
                  "type": "array"
                },
                "k": {
                  "description": "how many to pick, 1..1000 (default 1; alias count). Without replacement k <= items.length",
                  "type": "integer"
                },
                "replace": {
                  "description": "true = with replacement (an item can win twice); default false",
                  "type": "boolean"
                },
                "request_id": {
                  "description": "your own tag; mixed into the DRNG seed",
                  "type": "string"
                },
                "weights": {
                  "description": "one non-negative INTEGER weight per item (floats rejected: the cumulative search must be recomputable exactly)",
                  "type": "array"
                }
              },
              "required": [
                "items"
              ],
              "type": "object"
            },
            "bodyType": {
              "enum": [
                "json"
              ],
              "type": "string"
            },
            "method": {
              "enum": [
                "POST"
              ],
              "type": "string"
            },
            "type": {
              "const": "http",
              "type": "string"
            }
          },
          "required": [
            "type",
            "method"
          ],
          "type": "object"
        },
        "output": {
          "properties": {
            "example": {},
            "type": {
              "type": "string"
            }
          },
          "required": [
            "type"
          ],
          "type": "object"
        }
      },
      "required": [
        "input"
      ],
      "type": "object"
    }
  },
  "discovery": {
    "discoverable": true,
    "info": {
      "entropy": {
        "attested": false,
        "health_passed": true,
        "is_hardware": false,
        "is_quantum": false,
        "min_entropy_per_byte": 7.7704,
        "model": "os.urandom CSPRNG",
        "note": "observed on the gateway's own readiness draw, published unpaid so the trust model is knowable before purchase; the same fields ride verbatim on every paid response",
        "observed_at": "2026-08-20T04:13:09.473Z",
        "signer_backend": "software",
        "source": "software-fallback",
        "vendor": "os"
      },
      "input": {
        "bodyFields": {
          "indices_only": {
            "description": "omit the picked items and return only their 0-based indices — use it when the items are large: the response cap is 4000000 bytes and with replace:true the same item can be emitted k times",
            "required": false,
            "type": "boolean"
          },
          "items": {
            "description": "candidates, 1..10000 entries (any JSON values)",
            "required": true,
            "type": "array"
          },
          "k": {
            "description": "how many to pick, 1..1000 (default 1; alias count). Without replacement k <= items.length",
            "required": false,
            "type": "integer"
          },
          "replace": {
            "description": "true = with replacement (an item can win twice); default false",
            "required": false,
            "type": "boolean"
          },
          "request_id": {
            "description": "your own tag; mixed into the DRNG seed",
            "required": false,
            "type": "string"
          },
          "weights": {
            "description": "one non-negative INTEGER weight per item (floats rejected: the cumulative search must be recomputable exactly)",
            "required": false,
            "type": "array"
          }
        },
        "bodyType": "json",
        "method": "POST",
        "type": "http"
      },
      "output": {
        "description": "result {picked (omitted when indices_only), indices, k, replace, weighted}, randomness, source, health, attestation, verification, derivation {rules, steps, recompute?}, payment metadata",
        "type": "json"
      }
    }
  }
}

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

null

Examples

curl

curl "https://animica.dev/x402/random/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://animica.dev/x402/random/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://animica.dev/x402/random/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: animica.dev
Endpoint: https://animica.dev/x402/random/pick
Machine-readable: /resources/7536.json