# StackGo Contact API

Extract structured public business contact information from any public business website. Returns company name, emails, phone numbers, social profiles, postal addresses, and contact pages as structured JSON. $0.01 per request via x402 on Base.

Paid endpoint: POST /api/v1/extract-contact
Price: $0.01 per request (x402 pay-per-request)
Network: eip155:8453 (Base mainnet)
Payment scheme: exact
Asset: USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913)

Usage: POST /api/v1/extract-contact with Content-Type: application/json and exactly this JSON body: {"url":"https://api.stackgoai.com/test-fixtures/contact-page"}
Do not send form data, query parameters, or additional body fields. Invalid request shapes return HTTP 400 before payment; valid unpaid requests return HTTP 402 with JSON body {} and the x402 v2 requirements in PAYMENT-REQUIRED.
After authorizing those exact requirements, retry the same request once with PAYMENT-SIGNATURE. Never retry or spend automatically when the payment outcome is ambiguous.
Returns: structured JSON with company name, emails, phones, social links, postal addresses, contact pages, and scanned pages.

Agent capability: contact.extract (bounded metadata-only description; not MCP protocol/transport; invokes the same paid endpoint, not a second execution route).
Discovery: GET /openapi.json (OpenAPI contract), GET /.well-known/x402.json (payment metadata), GET /.well-known/mcp.json (bounded metadata-only agent description)
Free routes: GET /api/health, GET /api/healthz

Contact: contact@stackgoai.com