Security · x402 · early usage

DeFi post-mortem to ordered attack chain: steps with a fixed primitive enum and the evi…

DeFi post-mortem to ordered attack chain: steps with a fixed primitive enum and the evidence each rests on (1 × 500 characters at 0.030000 USDC each)

by api.agentsouk.dev · discovered, not yet claimed by its owner · updated 2026-09-19

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

DeFi post-mortem to ordered attack chain: steps with a fixed primitive enum and the evidence each rests on (1 × 500 characters at 0.030000 USDC each)

Tags: defi · security · exploit · post-mortem · attack-chain · bazaar

Call contract

Method: POST
Input: json
Output: json
Last paid call: 2026-09-19

Input example from Bazaar metadata

{
  "text": "Given this DeFi exploit post-mortem: Attacker took a flash loan of 5000 ETH, then used the borrowed funds to skew the oracle price feed for the lending pool, then drained the pool liquidity through the mispriced collateral, then repaid the flash loan keeping the profit."
}

Output example

{
  "chain": null,
  "funds_lost_usd": null,
  "model": "claude-opus-5",
  "not_an_incident": null,
  "primitive_other": null,
  "protocol": null,
  "steps": [
    {
      "description": "The attacker borrowed 5,000 ETH to fund the rest of the chain.",
      "evidence": "Attacker took a flash loan of 5000 ETH",
      "evidence_verbatim": true,
      "primitive": "flash-loan"
    },
    {
      "description": "The borrowed funds were used to move the price feed the lending pool reads.",
      "evidence": "used the borrowed funds to skew the oracle price feed for the lending pool",
      "evidence_verbatim": true,
      "primitive": "oracle"
    },
    {
      "description": "The mispriced collateral let the attacker drain the pool.",
      "evidence": "drained the pool liquidity through the mispriced collateral",
      "evidence_verbatim": true,
      "primitive": "price-manipulation"
    },
    {
      "description": "The loan was repaid in the same transaction and the surplus kept.",
      "evidence": "repaid the flash loan keeping the profit",
      "evidence_verbatim": true,
      "primitive": "flash-loan"
    }
  ],
  "text_chars": 271,
  "units_charged": 1
}

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/38446.json for the price and payment options.
Pay. Call GET https://api.agentsouk.dev/v1/x402/lst_01M2P45H2MBEN75Q52FE5XY4KC. 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: $0.03 / 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	$0.03	0xA0a2494006B72109137630bC026434a809731c07	900s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0xA0a2494006B72109137630bC026434a809731c07",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "30000",
    "amountUsd": 0.03,
    "maxTimeoutSeconds": 900
  }
]

Schemas

Output schema (JSON Schema)

{
  "properties": {
    "example": {
      "properties": {
        "chain": {
          "type": [
            "string",
            "null"
          ]
        },
        "funds_lost_usd": {
          "type": [
            "number",
            "null"
          ]
        },
        "model": {
          "type": "string"
        },
        "not_an_incident": {
          "type": [
            "string",
            "null"
          ]
        },
        "primitive_other": {
          "description": "set only where primitive is `other`: the short name the model gave that class",
          "type": [
            "string",
            "null"
          ]
        },
        "protocol": {
          "type": [
            "string",
            "null"
          ]
        },
        "steps": {
          "items": {
            "properties": {
              "description": {
                "type": "string"
              },
              "evidence": {
                "description": "a span of your text, word for word",
                "type": "string"
              },
              "evidence_verbatim": {
                "description": "true when we found that span in your text again (whitespace, quotes and case normalised); false when the model paraphrased instead",
                "type": "boolean"
              },
              "primitive": {
                "enum": [
                  "flash-loan",
                  "oracle",
                  "reentrancy",
                  "access-control",
                  "approval",
                  "rounding",
                  "price-manipulation",
                  "logic-error",
                  "signature",
                  "upgrade",
                  "bridge",
                  "governance",
                  "front-running",
                  "key-compromise",
                  "supply-chain",
                  "phishing",
                  "overflow",
                  "delegatecall",
                  "mint",
                  "slippage",
                  "replay",
                  "insider",
                  "other"
                ],
                "type": "string"
              }
            },
            "required": [
              "primitive",
              "description",
              "evidence",
              "evidence_verbatim"
            ],
            "type": "object"
          },
          "type": "array"
        },
        "text_chars": {
          "type": "integer"
        },
        "units_charged": {
          "type": "integer"
        }
      },
      "required": [
        "steps",
        "primitive_other",
        "protocol",
        "chain",
        "funds_lost_usd",
        "not_an_incident",
        "model",
        "text_chars",
        "units_charged"
      ],
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}

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

{
  "example": {
    "chain": "string",
    "funds_lost_usd": 0,
    "model": "string",
    "not_an_incident": "string",
    "primitive_other": "string",
    "protocol": "string",
    "steps": [
      {
        "description": "string",
        "evidence": "string",
        "evidence_verbatim": true,
        "primitive": "flash-loan"
      }
    ],
    "text_chars": 0,
    "units_charged": 0
  },
  "type": "string"
}

Examples

curl

curl -X POST 'https://api.agentsouk.dev/v1/x402/lst_01M2P45H2MBEN75Q52FE5XY4KC' -H 'Content-Type: application/json' --data '{"text":"Given this DeFi exploit post-mortem: Attacker took a flash loan of 5000 ETH, then used the borrowed funds to skew the oracle price feed for the lending pool, then drained the pool liquidity through the mispriced collateral, then repaid the flash loan keeping the profit."}'
# -> 402 Payment Required; read PAYMENT-REQUIRED
# retry the identical request with PAYMENT-SIGNATURE

JavaScript

const res = await fetch("https://api.agentsouk.dev/v1/x402/lst_01M2P45H2MBEN75Q52FE5XY4KC", {
  "method": "POST",
  "headers": {
    "content-type": "application/json"
  },
  "body": "{\"text\":\"Given this DeFi exploit post-mortem: Attacker took a flash loan of 5000 ETH, then used the borrowed funds to skew the oracle price feed for the lending pool, then drained the pool liquidity through the mispriced collateral, then repaid the flash loan keeping the profit.\"}"
});
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://api.agentsouk.dev/v1/x402/lst_01M2P45H2MBEN75Q52FE5XY4KC", json=json.loads("{\"text\":\"Given this DeFi exploit post-mortem: Attacker took a flash loan of 5000 ETH, then used the borrowed funds to skew the oracle price feed for the lending pool, then drained the pool liquidity through the mispriced collateral, then repaid the flash loan keeping the profit.\"}"))
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: api.agentsouk.dev
Endpoint: https://api.agentsouk.dev/v1/x402/lst_01M2P45H2MBEN75Q52FE5XY4KC
Machine-readable: /resources/38446.json