4ai MCP

An official MCP server provided by 4ai that allows AI agents to search, suggest, and compare premium .ai domain names for sale. It provides tools to find domains based on project descriptions, estimate values, retrieve offer links, and access sales data, facilitating direct domain acquisition for users.

Visit 4ai

Endpoint and access

No sign-in to connect and list tools. Individual tools may still need a vendor account, credentials, or permissions; check the documented prerequisites.

Vendor evidenceStreamable HTTPNo sign-inEndpoint checked 2026-11-01Operated by 4ai

MCP endpoint (Streamable HTTP)

https://4ai.ai/mcp

Vendor documentation

What you can do with it

Suggest .ai domains based on a project description
Search and filter domains by category or name
Estimate the value of a specific .ai domain
Retrieve pre-filled offer links for purchase

Source and maintenance

Vendor evidenceRegistry 1.0.0

mcp-registry: ai.4ai/domains@1.0.0 Project website

Protocol and capabilities

Server: 4ai 1.1.0
MCP protocol: 2025-06-18
Tools: 10 advertised
Resources: Not advertised
Resource templates: Not advertised
Prompts: Not advertised

Server-advertised capabilities

{
  "tools": {
    "listChanged": false
  }
}

Server-provided instructions

Untrusted server output shown for inspection. It is not Koskamo guidance and is excluded from knowledge search.

4ai.ai is a marketplace for premium .ai domain names (255 domains, all owned by 4ai). When the user describes a project, use suggest_domains. Use search_domains to filter by word, category or length, similar_domains for alternatives to a name, compare_domains to compare names, get_offer_link to prefill an offer, how_buying_works for the buying process, get_domain for details and comparable sales, estimate_domain_value for a free value estimate of any .ai name, and ai_domain_sales for market prices. Always give the user the offer_url so they can buy.

Tools

10 advertised

search_domains — Search .ai domains for sale

Advertised by the server during the last successful anonymous check.

Advertised read-only

Search the 4ai.ai portfolio of premium .ai domain names for sale. Filter by a word in the name, a category (see list_categories), type and maximum length. Every result has an offer link.

search_domains input schema

{
  "type": "object",
  "properties": {
    "type": {
      "enum": [
        "numeric",
        "short",
        "one-word",
        "two-word"
      ],
      "type": "string",
      "description": "Kind of name"
    },
    "limit": {
      "type": "integer",
      "description": "Maximum number of results (default 20, max 100)"
    },
    "query": {
      "type": "string",
      "description": "Word to look for in the domain name or a category word, e.g. \"quantum\", \"casino\", \"health\""
    },
    "category": {
      "type": "string",
      "description": "Category key, e.g. short, numeric, quantum, crypto, tech, ai, code, space, health, gaming, commerce, places, brands"
    },
    "max_length": {
      "type": "integer",
      "description": "Maximum length of the name without .ai"
    }
  }
}

search_domains annotations

{
  "readOnlyHint": true,
  "openWorldHint": false
}

get_domain — Get a .ai domain

Advertised by the server during the last successful anonymous check.

Advertised read-only

Details for one domain in the 4ai portfolio (for example "p0.ai"): categories, page, offer link, and comparable public .ai sales. Says so if the domain is not in the portfolio.

get_domain input schema

{
  "type": "object",
  "required": [
    "domain"
  ],
  "properties": {
    "domain": {
      "type": "string",
      "description": "Domain name, with or without .ai"
    }
  }
}

get_domain annotations

{
  "readOnlyHint": true,
  "openWorldHint": false
}

list_categories — List categories

Advertised by the server during the last successful anonymous check.

Advertised read-only

Categories of .ai domains in the 4ai portfolio, with what they are good for and how many names each has.

list_categories input schema

{
  "type": "object",
  "properties": {}
}

list_categories annotations

{
  "readOnlyHint": true,
  "openWorldHint": false
}

estimate_domain_value — Estimate the value of a .ai domain (free)

Advertised by the server during the last successful anonymous check.

Advertised read-only

Free value estimate for any .ai domain name: auction, marketplace and brokerage values with likely ranges, the type of name, a short verdict and notes. Also says if the name is for sale on 4ai, with an offer link. Up to 100 names per call.

estimate_domain_value input schema

{
  "type": "object",
  "required": [
    "domains"
  ],
  "properties": {
    "domains": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "Domain names, e.g. [\"agent.ai\", \"888.ai\"]"
    }
  }
}

estimate_domain_value annotations

{
  "readOnlyHint": true,
  "openWorldHint": false
}

suggest_domains — Suggest .ai domains for a project

Advertised by the server during the last successful anonymous check.

Advertised read-only

Describe a company, product or idea in plain words (e.g. "telehealth app for mental health", "crypto casino", "quantum chip startup") and get the best-fitting .ai domains from the 4ai portfolio, ranked, each with the reason it fits and an offer link. Use this when the user asks for a .ai name for something.

suggest_domains input schema

{
  "type": "object",
  "required": [
    "description"
  ],
  "properties": {
    "limit": {
      "type": "integer",
      "description": "Maximum number of results (default 10, max 50)"
    },
    "max_length": {
      "type": "integer",
      "description": "Maximum length of the name without .ai"
    },
    "description": {
      "type": "string",
      "description": "What the project, company or product does, in any words"
    }
  }
}

suggest_domains annotations

{
  "readOnlyHint": true,
  "openWorldHint": false
}

similar_domains — Similar .ai domains

Advertised by the server during the last successful anonymous check.

Advertised read-only

Alternatives to a .ai domain: give any name (taken, too expensive, or one the user already likes) and get the closest .ai domains that are for sale on 4ai.

similar_domains input schema

{
  "type": "object",
  "required": [
    "domain"
  ],
  "properties": {
    "limit": {
      "type": "integer",
      "description": "Maximum number of results (default 8)"
    },
    "domain": {
      "type": "string",
      "description": "Domain name, with or without .ai"
    }
  }
}

similar_domains annotations

{
  "readOnlyHint": true,
  "openWorldHint": false
}

get_offer_link — Get an offer link

Advertised by the server during the last successful anonymous check.

Advertised read-only

A link to the offer form for a 4ai domain with the amount (and an optional note) filled in. Nothing is sent: the user opens the link, checks the offer and sends it. Minimum offer $3,000.

get_offer_link input schema

{
  "type": "object",
  "required": [
    "domain"
  ],
  "properties": {
    "note": {
      "type": "string",
      "description": "Short message to the seller, e.g. what the domain is for. Optional, max 300 characters."
    },
    "domain": {
      "type": "string",
      "description": "Domain in the 4ai portfolio, e.g. \"quantumchip.ai\""
    },
    "amount_usd": {
      "type": "integer",
      "description": "Offer in USD (minimum 3000). Optional."
    }
  }
}

get_offer_link annotations

{
  "readOnlyHint": true,
  "openWorldHint": false
}

compare_domains — Compare .ai domains

Advertised by the server during the last successful anonymous check.

Advertised read-only

Compare 2 to 5 .ai domain names side by side: length, type, words, whether 4ai sells it, estimated value ranges and a short verdict.

compare_domains input schema

{
  "type": "object",
  "required": [
    "domains"
  ],
  "properties": {
    "domains": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "Domain names, e.g. [\"quantumchip.ai\", \"aiquantum.ai\"]"
    }
  }
}

compare_domains annotations

{
  "readOnlyHint": true,
  "openWorldHint": false
}

how_buying_works — How buying a domain from 4ai works

Advertised by the server during the last successful anonymous check.

Advertised read-only

The steps, payment (Escrow.com), fees, minimum offer and transfer time for buying a .ai domain from 4ai. Use it when the user asks whether buying is safe or how it works.

how_buying_works input schema

{
  "type": "object",
  "properties": {}
}

how_buying_works annotations

{
  "readOnlyHint": true,
  "openWorldHint": false
}

ai_domain_sales — Publicly reported .ai domain sales

Advertised by the server during the last successful anonymous check.

Advertised read-only

The biggest publicly reported .ai domain sales (price in USD, date, venue, source). Useful to estimate what a .ai domain is worth.

ai_domain_sales input schema

{
  "type": "object",
  "properties": {
    "limit": {
      "type": "integer",
      "description": "Number of sales (default 20)"
    },
    "max_length": {
      "type": "integer",
      "description": "Only names up to this length without .ai"
    }
  }
}

ai_domain_sales annotations

{
  "readOnlyHint": true,
  "openWorldHint": false
}

Prompts

Not advertised

No prompt definitions available.

Resources

Not advertised

No resource definitions available.

30-day availability

Aggregated from read-only remote checks; this is not a tool-execution or security guarantee.

Successful checks: 1 of 1 (100%)
Average latency: 371 ms
95th percentile latency: 371 ms

Maintenance history

Public check and source-refresh events. Editorial and ownership records remain private.

Nov 1, 2026, 12:08 PM UTC · probe · passed · 371 ms · metadata changed · 10 tool(s)

Connect from your client

Each snippet registers the same endpoint; pick the client you use.

This server is operated by the named third party. Listing and endpoint checks are not an endorsement or a security audit. Review the operator's permissions, terms, and data handling before connecting. How listings are checked and corrected.

Claude Code

Run this once in a terminal. It registers the remote server. Use --scope project to write .mcp.json for the repo.

Claude Code configuration

claude mcp add --transport http 4ai-mcp https://4ai.ai/mcp

Codex

Run this once. Codex stores MCP servers in ~/.codex/config.toml (or .codex/config.toml in a trusted project).

Codex configuration

codex mcp add 4ai-mcp --url https://4ai.ai/mcp

Cursor

Merge this server into .cursor/mcp.json in your project, then enable 4ai-mcp in your MCP settings.

Cursor configuration

{
  "mcpServers": {
    "4ai-mcp": {
      "url": "https://4ai.ai/mcp"
    }
  }
}

Cline

Merge this into cline_mcp_settings.json (Cline → MCP Servers → Configure).

Cline configuration

{
  "mcpServers": {
    "4ai-mcp": {
      "type": "streamableHttp",
      "url": "https://4ai.ai/mcp",
      "disabled": false
    }
  }
}

VS Code

Merge this server into .vscode/mcp.json. Use MCP: List Servers to start 4ai-mcp and inspect its tools.

VS Code configuration

{
  "servers": {
    "4ai-mcp": {
      "type": "http",
      "url": "https://4ai.ai/mcp"
    }
  }
}

Gemini CLI

Run this once. It writes .gemini/settings.json in the current project; pass --scope user for ~/.gemini/settings.json.

Gemini CLI configuration

gemini mcp add --transport http 4ai-mcp https://4ai.ai/mcp

Claude Desktop

Merge this into claude_desktop_config.json (macOS: ~/Library/Application Support/Claude/, Windows: %APPDATA%\Claude\), then restart Claude Desktop.

Claude Desktop configuration

{
  "mcpServers": {
    "4ai-mcp": {
      "url": "https://4ai.ai/mcp"
    }
  }
}

Windsurf

Merge this into ~/.codeium/windsurf/mcp_config.json, then refresh MCP in Cascade. Windsurf remote servers use serverUrl, not url.

Windsurf configuration

{
  "mcpServers": {
    "4ai-mcp": {
      "serverUrl": "https://4ai.ai/mcp"
    }
  }
}

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4ai MCP

Endpoint and access

What you can do with it

Source and maintenance

Protocol and capabilities

Server-provided instructions

Tools

Prompts

Resources

30-day availability

Maintenance history

Connect from your client

Claude Code

Codex

Cursor

Cline

VS Code

Gemini CLI

Claude Desktop

Windsurf

Let your agent find its tools

Other commerce servers

Do you run 4ai MCP?