openapi: 3.2.0 info: title: BuiltWith API (from llms.txt + samples) Ask API version: '2026-05-08' description: OpenAPI spec generated from https://api.builtwith.com/llms.txt and sample payloads under https://api.builtwith.com/samples/*.json (where available). Endpoints not covered by a sample file use a generic JSON schema. servers: - url: https://api.builtwith.com security: - ApiKeyQuery: [] tags: - name: Ask paths: /ask1/api.json: get: operationId: ask_v1 tags: - Ask summary: Ask API description: Natural language website list queries. MCP OpenAI/ChatGPT requests are served as preview results and do not send COMMIT=true. parameters: - $ref: '#/components/parameters/query' - $ref: '#/components/parameters/commit' - $ref: '#/components/parameters/nextOffset' - $ref: '#/components/parameters/meta' responses: '200': description: OK content: application/json: schema: $ref: '#/components/schemas/AskApiV1Response' components: parameters: meta: name: META in: query required: false schema: type: boolean default: false description: Set true to include metadata in Ask API results. commit: name: COMMIT in: query required: false schema: type: boolean default: false description: For Ask API, set true to request a committed/full report. OpenAI MCP requests ignore this and stay in preview mode. query: name: QUERY in: query required: true schema: type: string description: Search query. nextOffset: name: NEXTOFFSET in: query required: false schema: type: string description: Pagination offset from the previous response's NextOffset. schemas: AskApiV1Response: type: object properties: Results: type: array items: type: object additionalProperties: true NextOffset: type: string additionalProperties: true securitySchemes: ApiKeyQuery: type: apiKey in: query name: KEY description: BuiltWith API key (KEY). BearerAuth: type: http scheme: bearer description: BuiltWith API key or temporary bw- agent token in the Authorization header. externalDocs: description: 'Source: BuiltWith llms.txt' url: https://api.builtwith.com/llms.txt x-mcp: endpoint: https://api.builtwith.com/mcp server: builtwith version: 1.3.0 transport: streamable-http tools: - domain-lookup - domain-api - domain-api-json - change-api - relationships-api - free-api - company-to-url - tags-api - recommendations-api - redirects-api - keywords-api - keywords-search-api - trends-api - product-api - trust-api - financial-api - social-api - payment-balance - payment-config - payment-purchase - vector-api - ask-api - ask-api-json resources: - ui://widget/domain-technologies.html - ui://widget/ask-sites.html prompts: - analyze-tech-stack - find-related-websites - get-technology-recommendations - research-company - check-domain-trust - discover-technologies-by-concept x-live-feed-websocket: tag: LiveFeed servers: - url: wss://sync.builtwith.com connection_endpoints: - wss://sync.builtwith.com/wss/new?KEY=YOUR_KEY - wss://sync.builtwith.com/wss/channel/{TECH}?KEY=YOUR_KEY commands: - action: subscribe payload: action: subscribe channel: Shopify - action: unsubscribe payload: action: unsubscribe channel: Shopify - action: list_subscriptions payload: action: list_subscriptions