Free API and MCP

The essentials

• Free: no key, no account, no paid tier behind it.
• CC BY 4.0 licence: free reuse of the factual data, with attribution (see below).
• REST API: https://vuntum.com/api/v1, read-only, JSON, 120 requests per minute per IP address. OpenAPI 3.1 description: openapi.json.
• MCP server: https://vuntum.com/mcp (Streamable HTTP), read-only, 16 tools, 60 requests per minute per IP address. Nothing to install.
• Two languages: texts are in French by default, in English with ?lang=en (API) or locale: "en" (MCP).

Sample API requests

Each example can be pasted as is in a terminal. Every response has the same shape: data (the result), meta (date, licence, attribution) and, for lists, a pagination cursor. Add limit= to shorten a list.

Every endpoint, its parameters and its error codes are described in openapi.json. Responses carry an ETag and accept conditional requests; errors follow RFC 9457.

The MCP server

MCP (Model Context Protocol) is the standard plug that lets an AI assistant query a data source. Once Vuntum is added as a connector, the assistant answers from our sourced data rather than from memory, and points to the sheet to read. The address to give is always the same: https://vuntum.com/mcp, with no authentication.

Questions to ask your assistant

A few examples, by theme, that call on the server’s tools.

• Find
  • Which robots can climb stairs, and who says so?
  • Which home robots can I program in Python or ROS 2?
  • Which open-source humanoid robotics projects does Vuntum list?
• Compare
  • Compare the Unitree G1 and the Unitree H1: what differs, and what is not disclosed?
  • Among these three robots, which has the best evidence for its battery life?
• Prices and availability
  • What does the Unitree G1 cost in the US and in China, and when was that price seen?
  • Is this robot on sale in Europe today?
• Check
  • Where does this battery figure come from, and is it claimed by the maker or measured by a third party?
  • Explain how Vuntum ranks its levels of evidence.
• Follow
  • What changed in the database this week?
  • Which recent Vuntum articles are about humanoid robots?

MCP clients: what we tested

We separate what we ran ourselves from what we copy from the client’s documentation. The tests were run from a server on 3 October 2026, against the server’s public address (not a local copy).

Tested by us

Claude Code

Tested: works. The server was added to Claude Code, which called the price tool on the Unitree G1 and answered with both prices (China and US) and their date. One command is enough:

claude mcp add --transport http vuntum https://vuntum.com/mcp

Or, for a project, in the .mcp.json file:

{
  "mcpServers": {
    "vuntum": {
      "type": "http",
      "url": "https://vuntum.com/mcp"
    }
  }
}

Claude Desktop, through the configuration file (mcp-remote bridge)

Bridge tested: works. Claude Desktop reads this file to start a local program; the mcp-remote bridge connects that program to the remote server. We tried the bridge itself (16 tools listed, one successful call), but not the Claude Desktop application. Node.js is required. In Settings > Developer > Edit Config, add:

{
  "mcpServers": {
    "vuntum": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://vuntum.com/mcp"
      ]
    }
  }
}

Your own program (official SDK)

Tested: works. With the official TypeScript SDK (@modelcontextprotocol/sdk), twenty lines are enough to list the tools and call one. A ready-to-run example and a check are in the server’s public repository.

Documented setup, not yet tested by us

We cannot open these applications from our server. The settings below follow their documentation; if one does not work for you, tell us and we will correct the page.

claude.ai and Claude Desktop (custom connector)

In Customize > Connectors, choose Add custom connector, paste the address https://vuntum.com/mcp, leave authentication empty, then confirm. In a conversation, turn it on from the + menu, under Connectors. On Team and Enterprise plans, an organization owner adds it first.

ChatGPT

Remote MCP servers need developer mode (Settings > Security and login > Developer mode, on plans that offer it). Then create an app with the address https://vuntum.com/mcp and No authentication. Menu names change often at OpenAI: follow its developer mode guide.

Cursor

In ~/.cursor/mcp.json (or .cursor/mcp.json in a project):

{
  "mcpServers": {
    "vuntum": {
      "url": "https://vuntum.com/mcp"
    }
  }
}

VS Code

In .vscode/mcp.json:

{
  "servers": {
    "vuntum": {
      "type": "http",
      "url": "https://vuntum.com/mcp"
    }
  }
}

Limits to know

• Beyond 60 requests per minute per IP address, the MCP server answers 429 with Retry-After: 60; the API is limited to 120, with explicit RateLimit-* headers. A client session also counts opening and listing the tools.
• Only published data is served. A missing value means we have not found a reliable source yet, not that the answer is “no”.
• For heavy use, prefer the full export (JSON Lines or CSV) to thousands of requests.

Licence and attribution

The factual data is published under the CC BY 4.0 licence: you may copy, transform and redistribute it, commercially too, provided you credit the source. Articles, guides and analyses remain protected.

Expected credit: Source: Vuntum (https://vuntum.com), CC BY 4.0 licence, with a link to the sheet concerned.

For the rest (exports, llms.txt, dataset): Data and API. The MCP server is also listed in the protocol’s official registry as com.vuntum/mcp, and its public repository holds the code examples.