Conversor IAE-CNAE MCP server

Conversor IAE-CNAE — MCP Server

-22c55e.svg) <!-- Add once live: -->

The first fiscal MCP server for Spain. Connect any AI agent to live IAE, CNAE 2025, AEAT tax-form and RETA data — official sources, no scrapers.

6 tools free. No key. No signup. Add the endpoint and start asking.

This is the public manifest + docs repo for the hosted Conversor IAE-CNAE MCP server. The server runs at conversoriaecnae.es — there is nothing to install or self-host. This repo holds the server.json registry manifest, the connection details, the tool catalog, and copy-paste examples.

Why this exists

Autónomos and gestorías in Spain lose hours mapping IAE ↔ CNAE codes and guessing which AEAT forms (modelos 036/130/303/347…) apply to an activity. General-purpose AI agents make it worse: they confidently hallucinate tax facts that are wrong.

This server gives your agent a direct line to the real data — 1,187 IAE codes from the AEAT, 1,060 CNAE 2025 codes from the INE, the IAE↔CNAE crosswalk, módulos IRPF/IVA, AEAT obligations, and the 2026 RETA brackets — so it answers from official sources instead of guessing.

It is Spain-only, by design.

Connect in 30 seconds

The server speaks Streamable HTTP (MCP spec 2025-11-25; SSE is not exposed). Add it to your MCP client config:

{
  "mcpServers": {
    "conversor-iae-cnae": {
      "type": "streamable-http",
      "url": "https://www.conversoriaecnae.es/api/mcp/mcp"
    }
  }
}

For the 4 premium tools, add your cvr_ API key as a Bearer header inside the server block:

{
  "mcpServers": {
    "conversor-iae-cnae": {
      "type": "streamable-http",
      "url": "https://www.conversoriaecnae.es/api/mcp/mcp",
      "headers": { "Authorization": "Bearer cvr_your_api_key" }
    }
  }
}

Works with Claude Desktop / claude.ai (also available as a native connector), ChatGPT (developer-mode connectors), Cursor, Gemini CLI, and any MCP-compatible client.

• Cursor one-click: the "Add to Cursor" deeplink lives on the connect page.
• claude.ai connector: add https://www.conversoriaecnae.es/api/mcp/mcp as a custom connector (OAuth handles auth automatically).

The 10 tools

6 free (no key, no signup) · 4 premium (Profesional plan, from €29/mo — via a cvr_ key or Supabase OAuth).

Free vs premium

Shortened. The full README is on GitHub.