---
title: "Find websites related to a domain"
method: POST
path: "/agent/relationships"
tags: ["Company Research"]
---

# Find websites related to a domain

`POST /agent/relationships`

Find domains related through shared identifiers, infrastructure, analytics, ownership signals, and other BuiltWith relationship evidence.

## Request body

- object
  - `domain` string, required — Domain name to research, for example example.com. Do not include a URL path.

## Response `200`

BuiltWith result returned after payment settlement

- object — BuiltWith API JSON response. Fields vary by capability and available data.

## Other responses

- `400` — Invalid JSON input; verified payments are not settled for validation failures
- `402` — Payment Required
- `502` — The upstream BuiltWith API request failed; the verified payment is not settled
- `503` — x402 payments are not configured on this server

---

[API](https://skmtc.net/builtwith/apis/builtwith-x402-pay-per-call-api.md) · [All operations](https://skmtc.net/builtwith/apis/builtwith-x402-pay-per-call-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/builtwith/builtwith-x402-pay-per-call-api/revisions/128fc6ec8424/schema)