# Notsy Facturación Muse connector

From musedirectory.ai, the independent directory of Meta Muse connectors. Not affiliated with Meta.

## Notsy Facturación

Issue official Mexican tax invoices (CFDIs 4.0) and resolve SAT tax codes for your business.

- Record: https://musedirectory.ai/connector/notsy-facturacio-n
- Category: Finance & Bills
- Developer: Notsy (https://facturacion.notsy.com.mx/developers)
- Muse status: Extra setup. Not in Muse's Connectors list yet. Muse can still use it: its page gives you a request to paste into Muse.
- Health: Working, 1552ms, checked 2026-09-28T08:45:54Z
- Endpoint: https://mcp.notsy.com.mx/mcp
- Auth: Needs an access key; Pricing: unknown
- Screening: Screened, no issues found (2026-09-25T02:26:16Z)
- Source: Found in the official MCP Registry (io.github.HEUSAI/notsy-facturacion) https://registry.modelcontextprotocol.io/v0/servers?search=io.github.HEUSAI%2Fnotsy-facturacion

Connects to Mexico's SAT tax authority to issue and stamp official CFDIs 4.0. Resolves tax product codes, validates invoices before submission, calculates totals with IVA and withholdings, and tracks daily emission limits. Requires API key and Mexican business registration.

Example request: "Create and send an official invoice to a client for consulting services with the correct SAT tax classification and IVA."

How to connect: Not in Muse's Connectors list yet, but Muse can still use it. Paste this into Muse: "Use Notsy Facturación to help me. It is a free service with an MCP server at https://mcp.notsy.com.mx/mcp. It needs an API key from Notsy; ask me to enter it through your secure credential prompt. Ask me before you share anything with it." Muse asks before it shares anything with the app's site. Meta does not review apps used this way, so only use ones you trust. We tested this in the Muse app on September 24, 2026: Muse used an app's link directly this way and returned a live answer.

Tools:
- whoami: Confirma la identidad del agente: a qué negocio pertenece la API key, sus permisos (scopes), límites de emisión y uso del día. Úsalo para diagnosticar la conexión.
- resolver_claves_sat: Convierte una descripción en lenguaje natural a las claves del SAT necesarias para facturar. Devuelve `sugerencia` con clave_prodserv, clave_unidad, objeto_imp, tasa_iva y uso_cfdi, más `candidatos` por si quieres elegir otra. Llámalo antes de armar un concepto si no conoces las 
- preview_factura: DRY-RUN: valida la factura y calcula los totales (subtotal, IVA, retenciones, total) SIN timbrar, reservar ni cobrar. También devuelve la cotización canónica de créditos y el saldo proyectado. Úsalo SIEMPRE antes de emitir_cfdi para confirmar el monto, el costo y que los datos pa
- emitir_cfdi: Emite y timbra un CFDI 4.0 OFICIAL ante el SAT (acción real, con costo y difícil de revertir). Llama primero a preview_factura. El motor aplica los límites de la API key (puede requerir aprobación humana) y registra la acción en la bitácora. Args: iguales a preview_factura, más: 

Screening checks:
- MCP handshake: pass (Answered in 1389ms)
- Domain against threat feeds (Cloudflare security DNS): pass (mcp.notsy.com.mx, facturacion.notsy.com.mx not flagged)
- Published packages against the OSV malicious-package database: n/a (No npm or PyPI package published)
- Hidden instructions or invisible characters in tool text: pass (4 tools read, nothing found)
- Inputs asking for passwords, card numbers or seed phrases: pass (None found)
- Domain and redirects: pass (No redirects off the domain)
- AI review of purpose and tool behavior: pass (No concerns)