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openapi: 3.2.0
info:
title: BuiltWith x402 Pay-per-Call List Passes API
version: 1.0.0
description: Accountless pay-per-call website, company, and technology intelligence using x402 v2 and USDC on Base. AgentCash-compatible clients can discover and pay for every operation in this document.
contact:
name: BuiltWith Support
email: support@builtwith.com
url: https://builtwith.com/contact
x-guidance: For one-off agent research, choose the narrowest /agent operation and use its documented HTTP method and input. Every /agent operation costs $0.0495; GET /agent/domain accepts query parameters and the other /agent calls accept JSON bodies. No account, API key, payer field, or prepaid key is needed. Send the intended input on the first request, read the x402 v2 challenge from PAYMENT-REQUIRED, sign it for Base USDC, and retry the identical request with PAYMENT-SIGNATURE. Validation and upstream failures are not settled. Use /agent/company-domains before /agent/domain when only a company name is known, /agent/technology-search to resolve a concept to BuiltWith technology names, and /agent/ask for natural-language website discovery. High-volume callers may instead buy prepaid credits through the BuiltWith MCP server. Fixed-price List passes are separate products for List API and committed Ask access.
servers:
- url: https://api.builtwith.com
tags:
- name: List Passes
paths:
/x402/list-pass/basic:
post:
operationId: purchaseBasicListPass
summary: Purchase a 30-day basic BuiltWith List pass
description: Pay 295.00 USDC on Base for a bearer pass covering 2 primary technology reports and 2 keyword or committed Ask reports. Repeating an existing report does not consume another slot.
tags:
- List Passes
security: []
x-payment-info:
price:
mode: fixed
currency: USD
amount: '295.00'
protocols:
- x402: {}
requestBody:
required: false
content:
application/json:
schema:
type: object
additionalProperties: false
properties: {}
required: []
example: {}
responses:
'200':
description: Pass purchased and payment settled
headers:
PAYMENT-RESPONSE:
description: Base64-encoded x402 v2 settlement response.
schema:
type: string
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- passToken
- tier
- payer
- price
- expiresAt
- technologyReportLimit
- keywordReportLimit
- warning
properties:
passToken:
type: string
description: Secret bearer token. Store it securely; it is returned only once.
tier:
type: string
enum:
- basic
- pro
payer:
type: string
pattern: ^0x[a-fA-F0-9]{40}$
description: Base wallet recovered from the settled x402 payment.
price:
type: string
pattern: ^\$[0-9]+(?:\.[0-9]+)?$
expiresAt:
type: string
format: date-time
technologyReportLimit:
type: integer
minimum: 0
keywordReportLimit:
type: integer
minimum: 0
warning:
type: string
'400':
description: Invalid JSON input; verified payments are not settled for validation failures
'402':
description: Payment Required
headers:
PAYMENT-REQUIRED:
description: Base64-encoded x402 v2 payment requirements.
schema:
type: string
'502':
description: The upstream BuiltWith API request failed; the verified payment is not settled
'503':
description: x402 payments are not configured on this server
/x402/list-pass/pro:
post:
operationId: purchaseProListPass
summary: Purchase a 30-day pro BuiltWith List pass
description: Pay 495.00 USDC on Base for a bearer pass covering 50 primary technology reports and 50 keyword or committed Ask reports. Repeating an existing report does not consume another slot.
tags:
- List Passes
security: []
x-payment-info:
price:
mode: fixed
currency: USD
amount: '495.00'
protocols:
- x402: {}
requestBody:
required: false
content:
application/json:
schema:
type: object
additionalProperties: false
properties: {}
required: []
example: {}
responses:
'200':
description: Pass purchased and payment settled
headers:
PAYMENT-RESPONSE:
description: Base64-encoded x402 v2 settlement response.
schema:
type: string
content:
application/json:
schema:
type: object
additionalProperties: false
required:
- passToken
- tier
- payer
- price
- expiresAt
- technologyReportLimit
- keywordReportLimit
- warning
properties:
passToken:
type: string
description: Secret bearer token. Store it securely; it is returned only once.
tier:
type: string
enum:
- basic
- pro
payer:
type: string
pattern: ^0x[a-fA-F0-9]{40}$
description: Base wallet recovered from the settled x402 payment.
price:
type: string
pattern: ^\$[0-9]+(?:\.[0-9]+)?$
expiresAt:
type: string
format: date-time
technologyReportLimit:
type: integer
minimum: 0
keywordReportLimit:
type: integer
minimum: 0
warning:
type: string
'400':
description: Invalid JSON input; verified payments are not settled for validation failures
'402':
description: Payment Required
headers:
PAYMENT-REQUIRED:
description: Base64-encoded x402 v2 payment requirements.
schema:
type: string
'502':
description: The upstream BuiltWith API request failed; the verified payment is not settled
'503':
description: x402 payments are not configured on this server
externalDocs:
description: BuiltWith x402 USDC API documentation
url: https://api.builtwith.com/x402-api
x-discovery:
ownershipProofs:
- '0x1ce9d8b85fd8afc523d26bf39eb4080326e4bef016e430f327d1cf6779fcdfdd0302f8e8804599bb3b7e254f26cf7fa3bc6c1311f9c9ae190e0c70e37fb305c11b'
x-x402-discovery: https://api.builtwith.com/.well-known/x402
x-agentcash-guidance:
llmsTxtUrl: https://api.builtwith.com/llms.txt