Payments · x402 · early usage

Pay-per-Proof: one post-quantum ML-DSA-65 / Dilithium-3 (NIST FIPS 204) signature over…

Pay-per-Proof: one post-quantum ML-DSA-65 / Dilithium-3 (NIST FIPS 204) signature over your message/hash, x402-native.

by fractalai.net.co · discovered, not yet claimed by its owner · updated 2026-10-12

30d calls12

30d payers5

MethodPOST

Outputjson

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

Pay-per-Proof: one post-quantum ML-DSA-65 / Dilithium-3 (NIST FIPS 204) signature over your message/hash, x402-native.

Tags: signature · post-quantum · ml-dsa-65 · ai-agent · fips-204 · bazaar

Call contract

Method: POST
Input: json
Output: json
Last paid call: 2026-10-12

Input example from Bazaar metadata

{
  "message": "hello agent economy"
}

Output example

{
  "algorithm": "ml-dsa-65",
  "digest": "9f86…",
  "public_key": "BASE64_ML_DSA65_1952B",
  "signature": "BASE64_ML_DSA65_3309B"
}

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/33274.json for the price and payment options.
Pay. Call GET https://fractalai.net.co/api/x402/sign. 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, eip155:480, eip155:42220, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price: $0.02 / request
Protocol: x402 v2
Auth: No account or API key. Pay per request.
Networks: Base, Polygon, Arbitrum One, eip155:480, eip155:42220
Demand: 12 calls · 5 unique payers in 30d (public x402 Bazaar data)

x402 payment requirements

Scheme	Network	Asset	Amount	Pay to	Timeout
exact	Base eip155:8453	USDC	$0.02	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Base eip155:8453	USDC	$0.02	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Polygon eip155:137	0x12050c705152931cFEe3DD56c52Fb09Dea816C23	63890000000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Base eip155:8453	0xF197FFC28c23E0309B5559e7a166f2c6164C80aA	365100	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Arbitrum One eip155:42161	0xF197FFC28c23E0309B5559e7a166f2c6164C80aA	365100	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Polygon eip155:137	0xE6A537a407488807F0bbeb0038B79004f19DDDFb	99800000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Polygon eip155:137	0x4eD141110F6EeeAbA9A1df36d8c26f684d2475Dc	99800000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	eip155:480 eip155:480	0x0DC4F92879B7670e5f4e4e6e3c801D229129D90D	30340000000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Base eip155:8453	0x0DC4F92879B7670e5f4e4e6e3c801D229129D90D	30340000000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	eip155:480 eip155:480	0xD76f5Faf6888e24D9F04Bf92a0c8B921FE4390e0	99800000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Base eip155:8453	0xD76f5Faf6888e24D9F04Bf92a0c8B921FE4390e0	99800000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	eip155:480 eip155:480	0x337E7456B420bD3481e7FA61fA9850343d610d34	365100000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Base eip155:8453	0x337E7456B420bD3481e7FA61fA9850343d610d34	365100000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	eip155:480 eip155:480	0x8a1D45e102e886510e891d2Ec656a708991e2D76	63890000000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Base eip155:8453	0x8a1D45e102e886510e891d2Ec656a708991e2D76	63890000000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	Polygon eip155:137	0x55cF6b630d8AE6477DF63e194F0fd80ACFf05f86	63890000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	eip155:42220 eip155:42220	0x8A567e2aE79CA692Bd748aB832081C45de4041eA	63890000000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s
exact	eip155:42220 eip155:42220	0xe8537a3d056DA446677B9E9d6c5dB704EaAb4787	99800000000000000	0xC13789e82661635d9Cea38a53A0390CF9939ef4f	300s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "20000",
    "amountUsd": 0.02,
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "20000",
    "amountUsd": 0.02,
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:137",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x12050c705152931cFEe3DD56c52Fb09Dea816C23",
    "amount": "63890000000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0xF197FFC28c23E0309B5559e7a166f2c6164C80aA",
    "amount": "365100",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:42161",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0xF197FFC28c23E0309B5559e7a166f2c6164C80aA",
    "amount": "365100",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:137",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0xE6A537a407488807F0bbeb0038B79004f19DDDFb",
    "amount": "99800000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:137",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x4eD141110F6EeeAbA9A1df36d8c26f684d2475Dc",
    "amount": "99800000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:480",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x0DC4F92879B7670e5f4e4e6e3c801D229129D90D",
    "amount": "30340000000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x0DC4F92879B7670e5f4e4e6e3c801D229129D90D",
    "amount": "30340000000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:480",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0xD76f5Faf6888e24D9F04Bf92a0c8B921FE4390e0",
    "amount": "99800000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0xD76f5Faf6888e24D9F04Bf92a0c8B921FE4390e0",
    "amount": "99800000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:480",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x337E7456B420bD3481e7FA61fA9850343d610d34",
    "amount": "365100000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x337E7456B420bD3481e7FA61fA9850343d610d34",
    "amount": "365100000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:480",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x8a1D45e102e886510e891d2Ec656a708991e2D76",
    "amount": "63890000000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x8a1D45e102e886510e891d2Ec656a708991e2D76",
    "amount": "63890000000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:137",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x55cF6b630d8AE6477DF63e194F0fd80ACFf05f86",
    "amount": "63890000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:42220",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0x8A567e2aE79CA692Bd748aB832081C45de4041eA",
    "amount": "63890000000000000000",
    "maxTimeoutSeconds": 300
  },
  {
    "scheme": "exact",
    "network": "eip155:42220",
    "payTo": "0xC13789e82661635d9Cea38a53A0390CF9939ef4f",
    "asset": "0xe8537a3d056DA446677B9E9d6c5dB704EaAb4787",
    "amount": "99800000000000000",
    "maxTimeoutSeconds": 300
  }
]

Schemas

Output schema (JSON Schema)

{
  "properties": {
    "example": {
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}

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

{
  "example": {},
  "type": "string"
}

Examples

curl

curl "https://fractalai.net.co/api/x402/sign"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

JavaScript

const res = await fetch("https://fractalai.net.co/api/x402/sign");
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://fractalai.net.co/api/x402/sign")
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: fractalai.net.co
Endpoint: https://fractalai.net.co/api/x402/sign
Machine-readable: /resources/33274.json