Agent Service · x402 · early usage

Research brief

Research brief. Citations. Summarize research from the public web with key points and caveats. When to use: short cited answers for agent questions (fair-use snippets only — no full-text dumps). $0.08 per call in USDC on Base via x402 (cost-floored). No API k…

by x402.hydratrader.ai · discovered, not yet claimed by its owner · updated 2026-10-08

30d calls1

30d payers1

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

Tags: bazaar

Call contract

Method: POST
Input: json
Output: json
Last paid call: 2026-10-08

Input example from Bazaar metadata

{
  "depth": "quick",
  "question": "What is the x402 protocol and how do agents pay for APIs?",
  "scope": {
    "max_sources": 3
  }
}

Output example

{
  "brief": {
    "caveats": [
      "Ecosystem evolving quickly; always check live facilitator docs"
    ],
    "confidence": 0.78,
    "headline": "x402 turns HTTP 402 into USDC micropayments for agents",
    "key_points": [
      "Server returns 402 with payment terms; client pays and retries",
      "CDP Facilitator commonly used for verify/settle on Base",
      "Bazaar indexes discoverable paid routes"
    ],
    "summary": "x402 is an open payment protocol that uses HTTP 402 Payment Required so clients (including AI agents) can pay for web resources with stablecoins, commonly USDC on Base, via a facilitator that verifies and settles."
  },
  "citations": [
    {
      "published": null,
      "publisher": "Coinbase CDP",
      "snippet": "The x402 Bazaar is a catalog of payment-gated services discovered by the CDP Facilitator.",
      "title": "x402 Bazaar (Discovery Layer)",
      "url": "https://docs.cdp.coinbase.com/x402/buyer/discover-services"
    }
  ],
  "client_ref": null,
  "endpoint": "research-brief",
  "ok": true,
  "usage": {
    "floor_mult": 1.3,
    "latency_ms": 6400,
    "price_usdc": "0.08",
    "sources_used": 3,
    "token_cost_est_usdc": "0.05"
  }
}

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/32591.json for the price and payment options.
Pay. Call GET https://x402.hydratrader.ai/v1/research-brief. 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, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price: $0.08 / request
Protocol: x402 v2
Auth: No account or API key. Pay per request.
Networks: Base
Demand: 1 calls · 1 unique payers in 30d (public x402 Bazaar data)

x402 payment requirements

Scheme	Network	Asset	Amount	Pay to	Timeout
exact	Base eip155:8453	USDC	$0.08	0x55d06e282a699710e03088c218a9e79d2b1616fc	300s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x55d06e282a699710e03088c218a9e79d2b1616fc",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "80000",
    "amountUsd": 0.08,
    "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 -X POST 'https://x402.hydratrader.ai/v1/research-brief' -H 'Content-Type: application/json' --data '{"depth":"quick","question":"What is the x402 protocol and how do agents pay for APIs?","scope":{"max_sources":3}}'
# -> 402 Payment Required; read PAYMENT-REQUIRED
# retry the identical request with PAYMENT-SIGNATURE

JavaScript

const res = await fetch("https://x402.hydratrader.ai/v1/research-brief", {
  "method": "POST",
  "headers": {
    "content-type": "application/json"
  },
  "body": "{\"depth\":\"quick\",\"question\":\"What is the x402 protocol and how do agents pay for APIs?\",\"scope\":{\"max_sources\":3}}"
});
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
import json
res = httpx.request("POST", "https://x402.hydratrader.ai/v1/research-brief", json=json.loads("{\"depth\":\"quick\",\"question\":\"What is the x402 protocol and how do agents pay for APIs?\",\"scope\":{\"max_sources\":3}}"))
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: x402.hydratrader.ai
Endpoint: https://x402.hydratrader.ai/v1/research-brief
Machine-readable: /resources/32591.json