X4
Market Data · x402 · early usage

Detect whether an arbitrage opportunity exists in a set of token exchange rates (multi-…

Detect whether an arbitrage opportunity exists in a set of token exchange rates (multi-pool negative-cycle scan). Cheap boolean + magnitude signal for trading agents. POST a swap-rate graph, get back whether a profitable cycle exists and how large — without t…

by x402-solvers.onrender.com · discovered, not yet claimed by its owner · updated 2026-10-05

30d calls4
30d payers4
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

Detect whether an arbitrage opportunity exists in a set of token exchange rates (multi-pool negative-cycle scan). Cheap boolean + magnitude signal for trading agents. POST a swap-rate graph, get back whether a profitable cycle exists and how large — without the path.

Tags: defi · arbitrage · trading · signal · bazaar

Call contract

Method
POST
Input
json
Output
json
Last paid call
2026-10-05
Input example from Bazaar metadata
{
  "edges": [
    {
      "dex": "aerodrome",
      "fee": 0.0005,
      "from": "USDC",
      "rate": 0.00031,
      "to": "WETH"
    },
    {
      "dex": "uniswap",
      "fee": 0.0005,
      "from": "WETH",
      "rate": 3300,
      "to": "USDC"
    }
  ]
}
Output example
{
  "edgesEvaluated": 3,
  "hasArbitrage": true,
  "hops": 3,
  "nodesEvaluated": 3,
  "profitBucket": ">2%",
  "tier": "probe"
}

Use with an agent

  1. Discover. Agents find this listing with GET https://bazaar.saylorinnovations.com/discovery/search?query=…, the MCP tool search_resources, or /discovery/resources.
  2. Inspect. Fetch /resources/28708.json for the price and payment options.
  3. Pay. Call GET https://x402-solvers.onrender.com/v1/cycles/probe. The provider answers 402 with its payment requirements. An x402 client signs one of the options below and retries with PAYMENT-SIGNATURE.
  4. 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
$0.001 / request
Protocol
x402 v2
Auth
No account or API key. Pay per request.
Networks
Base
Demand
4 calls · 4 unique payers in 30d (public x402 Bazaar data)

x402 payment requirements

SchemeNetworkAssetAmountPay toTimeout
exactBase
eip155:8453
USDC$0.0010xA238AF2e66D9d7301F2D02932931851DdF900Dcd30s
accepts[] (raw JSON)
[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xA238AF2e66D9d7301F2D02932931851DdF900Dcd",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "1000",
    "amountUsd": 0.001,
    "maxTimeoutSeconds": 30
  }
]

Schemas

Output schema (JSON Schema)
{
  "properties": {
    "example": {
      "description": "Fast arbitrage-existence signal for a token swap graph: whether a profitable negative cycle exists and roughly how big, WITHOUT revealing the cycle path (that is the report tier).",
      "properties": {
        "edgesEvaluated": {
          "type": "number"
        },
        "hasArbitrage": {
          "description": "True if a profitable round-trip cycle exists.",
          "type": "boolean"
        },
        "hops": {
          "description": "Swaps in the detected cycle (0 if none).",
          "type": "number"
        },
        "nodesEvaluated": {
          "type": "number"
        },
        "profitBucket": {
          "description": "Coarse magnitude of the best cycle gross profit.",
          "enum": [
            "none",
            "<=0.1%",
            "0.1-0.5%",
            "0.5-2%",
            ">2%"
          ],
          "type": "string"
        },
        "tier": {
          "const": "probe"
        }
      },
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}
Example shape — generated from the schema, not a captured live response
{
  "example": {
    "edgesEvaluated": 0,
    "hasArbitrage": true,
    "hops": 0,
    "nodesEvaluated": 0,
    "profitBucket": "none",
    "tier": null
  },
  "type": "string"
}

Examples

curl
curl "https://x402-solvers.onrender.com/v1/cycles/probe"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid
JavaScript
const res = await fetch("https://x402-solvers.onrender.com/v1/cycles/probe");
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://x402-solvers.onrender.com/v1/cycles/probe")
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-solvers.onrender.com
Endpoint
https://x402-solvers.onrender.com/v1/cycles/probe
Machine-readable
/resources/28708.json