---
title: "4ai for AI Agents & Developers: MCP Server, API, Data | 4ai"
url: https://4ai.ai/for-ai-agents/
description: "Connect AI assistants to 4ai.ai: an MCP server, JSON data and an OpenAPI description for 254 premium .ai domains for sale and .ai sales records, plus embeddable widgets."
source: 4ai.ai, a marketplace for premium .ai domain names
---

# 4ai for AI agents & developers

Let AI assistants and apps find premium .ai domains for your users. 4ai offers an MCP server, open JSON data, an OpenAPI description and embeddable widgets. Free, read-only, no API key.

## MCP server

Connect any MCP client (streamable HTTP) to:

https://4ai.ai/mcp
Tools: **estimate_domain_value** (free value estimate for any .ai name), **search_domains** (by word, category, type, length), **get_domain** (details, offer link and comparable sales), **list_categories** and **ai_domain_sales** (publicly reported .ai sales). Every domain result includes an offer link, so the assistant can send the user straight to buying.

In Claude, add it as a custom connector (Settings → Connectors → Add custom connector) with the URL above. Other MCP-capable assistants and agent frameworks accept the same URL.

## Open data

- [/data/domains.json](https://4ai.ai/data/domains.json): all 254 domains for sale, with categories, type, what each is good for and offer links.

- [/data/ai-domain-sales.json](https://4ai.ai/data/ai-domain-sales.json) and [CSV](https://4ai.ai/data/ai-domain-sales.csv): publicly reported .ai sales with sources.

- [Registrations](https://4ai.ai/data/ai-domain-registrations.csv) and [Anguilla .ai revenue](https://4ai.ai/data/anguilla-ai-revenue.csv) (CSV).

- [/openapi.json](https://4ai.ai/openapi.json): OpenAPI 3.1 description, usable for GPT actions and tool calling.

- [/llms.txt](https://4ai.ai/llms.txt) and [/llms-full.txt](https://4ai.ai/llms-full.txt): plain-text summaries for language models.

The data is free to reuse under CC BY 4.0 with a link to 4ai.ai.

## Deep links

- Name ideas for a keyword: [/ai-domain-name-generator/?q=health](https://4ai.ai/ai-domain-name-generator/?q=health)

- Comparable sales for a name: [/ai-domain-value-estimator/?q=agent.ai](https://4ai.ai/ai-domain-value-estimator/?q=agent.ai)

- A domain page with offer form: `/domains/-ai/#make-offer`

## Widgets for your site

Biggest .ai sales:

.ai domains for sale on 4ai (optional category: short, numeric, quantum, crypto, tech, ai, code, space, health, gaming, commerce, places, brands):

<div data-4ai-domains="6" data-category="crypto"></div>
<script src="https://4ai.ai/widget/ai-sales.js" async></script>