paidfor

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Check an x402 seller before paying: verdict, failure rate and evidence from paid calls on Base.

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check_x402_seller Read-only

Call this before any x402 payment, before retrying a request that answered HTTP 402, or whenever the user is about to buy an API call with USDC on Base or names an API they intend to pay per call. Returns a verdict (avoid, caution, ok, unknown), one sentence to act on, the seller's paid-call count and failure rate with a 95% interval, listed price, modal quote and max overcharge ratio when known, and links to the seller page and raw evidence.

urlstring, required

x402 resource URL, or a bare seller domain such as api.example.com

Tools (4)

check_x402_seller

read-only

Argument	Type	Description
url*	string	x402 resource URL, or a bare seller domain such as api.example.com

Input schema (JSON)

{
  "type": "object",
  "$schema": "http://json-schema.org/draft-07/schema#",
  "required": [
    "url"
  ],
  "properties": {
    "url": {
      "type": "string",
      "minLength": 1,
      "description": "x402 resource URL, or a bare seller domain such as api.example.com"
    }
  }
}

list_reliable_sellers

Call this when choosing among sellers for a task, or when the user asks for a safe or reliable API. Returns sellers with zero failures across at least 30 paid calls, most-called first. For each: domain, category, paid-call count, the 95% upper bound on its failure rate, median quoted price in USDC, USDC paid to it in the last 30 days, when it was last seen, and its paidfor seller page.

read-only

Argument	Type	Description
limit	integer	How many sellers to return, most-called first; 50 when omitted
category	string	Kind of service to list sellers for; omit to list every kind

Input schema (JSON)

{
  "type": "object",
  "$schema": "http://json-schema.org/draft-07/schema#",
  "properties": {
    "limit": {
      "type": "integer",
      "maximum": 500,
      "minimum": 1,
      "description": "How many sellers to return, most-called first; 50 when omitted"
    },
    "category": {
      "enum": [
        "inference",
        "data",
        "scraping",
        "compute",
        "other"
      ],
      "type": "string",
      "description": "Kind of service to list sellers for; omit to list every kind"
    }
  }
}

recent_changes

Call this when the user asks what changed, or before relying on a verdict older than a day. Returns recent changes, newest first: verdict changes, new failures by type, moved quotes, changed pay-to addresses, sellers added or reaching 30 paid calls, published seller replies, the operator-reported series maturing or disagreeing with ours. Each change has its time, type, seller domain, seller page and type-specific details (for example the old and new quote).

read-only

Argument	Type	Description
host	string	Seller to show changes for, as a bare domain such as api.example.com; omit for every seller
since	string	Show only changes after this time, in ISO 8601 (such as the generated_at of a verdict you already have); omit for the latest changes

Input schema (JSON)

{
  "type": "object",
  "$schema": "http://json-schema.org/draft-07/schema#",
  "properties": {
    "host": {
      "type": "string",
      "minLength": 1,
      "description": "Seller to show changes for, as a bare domain such as api.example.com; omit for every seller"
    },
    "since": {
      "type": "string",
      "minLength": 1,
      "description": "Show only changes after this time, in ISO 8601 (such as the generated_at of a verdict you already have); omit for the latest changes"
    }
  }
}

report_x402_payment

After your agent pays an x402 seller with any wallet, report what came back. Needs the resource URL, the settlement transaction hash and the outcome. Free, no account, no key; the report counts only with on-chain proof.

Argument	Type	Description
url*	string	The x402 resource URL that was paid for
outcome*	string	What came back: ok (the response was usable for its purpose), non_delivery (an error, an empty body or nothing usable after paying), wrong_goods (a usable response, but not what was asked for), overcharge (charged more than the quoted or listed price), duplicate (two settlements for one purchase)
tx_hash*	string	The settlement transaction hash on Base: the `transaction` field of the seller's PAYMENT-RESPONSE or X-PAYMENT-RESPONSE header (base64 JSON)
http_status	integer	The HTTP status of the paid response, if known
quoted_usdc	any	The price the 402 quoted, in USDC, if known

Input schema (JSON)

{
  "type": "object",
  "$schema": "http://json-schema.org/draft-07/schema#",
  "required": [
    "url",
    "tx_hash",
    "outcome"
  ],
  "properties": {
    "url": {
      "type": "string",
      "format": "uri",
      "description": "The x402 resource URL that was paid for"
    },
    "outcome": {
      "enum": [
        "ok",
        "non_delivery",
        "wrong_goods",
        "overcharge",
        "duplicate"
      ],
      "type": "string",
      "description": "What came back: ok (the response was usable for its purpose), non_delivery (an error, an empty body or nothing usable after paying), wrong_goods (a usable response, but not what was asked for), overcharge (charged more than the quoted or listed price), duplicate (two settlements for one purchase)"
    },
    "tx_hash": {
      "type": "string",
      "pattern": "^0x[0-9a-fA-F]{64}$",
      "description": "The settlement transaction hash on Base: the `transaction` field of the seller's PAYMENT-RESPONSE or X-PAYMENT-RESPONSE header (base64 JSON)"
    },
    "http_status": {
      "type": "integer",
      "maximum": 599,
      "minimum": 100,
      "description": "The HTTP status of the paid response, if known"
    },
    "quoted_usdc": {
      "anyOf": [
        {
          "type": "number",
          "exclusiveMinimum": 0
        },
        {
          "type": "string",
          "pattern": "^\\d{1,12}(\\.\\d{1,6})?$"
        }
      ],
      "description": "The price the 402 quoted, in USDC, if known"
    }
  }
}

paidfor

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check_x402_seller Read-only

paidfor

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check_x402_seller Read-only

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Tools (4)

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