npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2026 – Pkg Stats / Ryan Hefner

keycae-mcp

v1.0.2

Published

MCP Server for KeyCAE - Argentine electronic invoicing (factura electrónica) with ARCA/AFIP

Readme

keycae-mcp 🔌

npm version npm downloads License: MIT

MCP Server for KeyCAE.arArgentine electronic invoicing (facturación electrónica) with ARCA/AFIP.

Let AI agents emit invoices, manage credentials, and handle delegations directly.

⚡ Quick Start

npx keycae-mcp

That's it. Your AI agent now has 10 tools for Argentine invoicing.

⚠️ Requisito: Delegación en ARCA

ANTES de facturar, debés delegar la facturación electrónica al representante de KeyCAE en ARCA:

  1. Ingresá a ARCA Clave Fiscal
  2. Buscá el servicio "Facturación Electrónica" (ws://wsfe)
  3. Delegá al CUIT representante: 20254459306 (Amilcar Waldemar Serra)
  4. Aceptá la relación de representación

Sin esta delegación, no podés emitir facturas. El MCP server te permite verificar el estado con check_delegation y solicitarla con request_delegation.

🔧 Configuration

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "keycae": {
      "command": "npx",
      "args": ["-y", "keycae-mcp"],
      "env": {
        "KEYCAE_API_KEY": "sk_live_..."
      }
    }
  }
}

Cursor / Windsurf

Add to .cursor/mcp.json in your project:

{
  "mcpServers": {
    "keycae": {
      "command": "npx",
      "args": ["-y", "keycae-mcp"],
      "env": {
        "KEYCAE_API_KEY": "sk_live_..."
      }
    }
  }
}

🛠️ Available Tools

| Tool | Description | |------|-------------| | emit_invoice | Emit an Argentine electronic invoice (A, B, C, M, E) | | get_invoice | Get details of a previously emitted invoice | | list_invoices | List recent invoices | | list_credentials | List digital certificates for the CUIT | | create_credential | Generate RSA keypair + CSR for ARCA | | check_delegation | Check ARCA delegation status | | request_delegation | Request ARCA delegation for invoicing | | lookup_taxpayer | Look up taxpayer by CUIT | | get_billing_status | Check billing plan and usage | | keycae_health | Health check |

💡 Example Usage

1. Check if ready to invoice

User: ¿Puedo facturar con el CUIT 20254459306?

Agent calls check_delegation → confirms delegation is active, then list_credentials → confirms certificate is valid.

2. Request delegation (if not done)

User: Necesito delegar mi facturación a KeyCAE

Agent calls request_delegation → starts the delegation process.

3. Emit a Factura B

User: Emití una factura B al CUIT 20333444555 por $15.000 ARS por "Servicios de consulting"

Agent calls emit_invoice:

{
  "cuit_emisor": "20254459306",
  "punto_de_venta": 3,
  "tipo_comprobante": "B",
  "receptor": { "tipo_doc": "CUIT", "nro_doc": "20333444555" },
  "conceptos": [{ "descripcion": "Servicios de consulting", "precio": 15000 }]
}

📋 Invoice Types

| Type | Description | When to use | |------|-------------|-------------| | A | IVA discriminado | RI → RI | | B | IVA incluido | RI → Consumidor Final | | C | Exento | No genera IVA | | M | Monotributo | Monotributo emitter | | E | Exportación | International clients |

🔗 Links

📦 Related Packages

📄 License

MIT