@ar-agents/facturacion

AFIP/ARCA factura electrónica (WSFE) for Vercel AI SDK 6+ agents.

Built for SaaS argentinos that need to:

• Emit Facturas A/B/C with the AFIP-issued CAE (Código de Autorización Electrónico)
• Auto-increment comprobante numbers via consultarUltimoAutorizado
• Verify previously-issued comprobantes
• Pre-validate locally to catch the 10 most common AFIP rejection reasons before the round-trip

Reuses the WSAA infrastructure from @ar-agents/identity: same X.509 cert, same TokenCache, same fetchWithRetry helper. If you already have @ar-agents/identity wired up, adding @ar-agents/facturacion is one cert-authorization step away.

Install

pnpm add @ar-agents/facturacion @ar-agents/identity
# peer deps: ai >=6, zod >=3

Setup

1. Generate cert + register alias as documented in @ar-agents/identity.
2. In ARCA → "Administrador de Relaciones de Clave Fiscal" → "Nueva Relación" → "AFIP" → "WebServices" → "Servicio Web de Facturación Electrónica" → select your alias.
3. Wire the client:

import { Experimental_Agent as Agent, stepCountIs } from "ai";
import { facturacionTools, WsfeClient } from "@ar-agents/facturacion";

const wsfe = new WsfeClient({
  certPath: process.env.AFIP_CERT_PATH!,
  keyPath: process.env.AFIP_KEY_PATH!,
  cuit: process.env.AFIP_CUIT!,
  env: "prod",
});

const agent = new Agent({
  model: "anthropic/claude-sonnet-4-6",
  tools: facturacionTools({ wsfe, defaultPtoVta: 1 }),
  stopWhen: stepCountIs(6),
});

const { text } = await agent.generate({
  prompt:
    "Emití una Factura C de $12.100 a Juan Pérez (CUIT 23-30900000-9), servicio del 1/5 al 31/5, vencimiento 15/6.",
});

The agent will: (1) consultar_ultimo_comprobante to get the next number, (2) emitir_factura, (3) report the CAE.

Tools

| Tool | Pure? | What it does | | ----------------------------- | -------- | ------------------------------------------------------ | | emitir_factura |: | Solicit a CAE for a new comprobante | | consultar_ultimo_comprobante|: | Get the last authorized number for (PtoVta, CbteTipo) | | consultar_factura_emitida |: | Look up a previously-issued comprobante | | obtener_tipos_comprobante |: | Live AFIP catalog of comprobante types | | obtener_tipos_documento |: | Live AFIP catalog of document types | | obtener_alicuotas_iva |: | Live AFIP catalog of IVA rates | | obtener_tipos_concepto |: | Live AFIP catalog of conceptos | | obtener_tipos_moneda |: | Live AFIP catalog of currencies | | obtener_cotizacion |: | AFIP exchange rate for a foreign currency vs ARS | | health_check_afip |: | AFIP WSFE app/db/auth status |

All 10 tools require a WsfeClient. Without one, they return { available: false, error: <setup instructions> } instead of crashing: drop-in safe for stub deployments.

For pure-algorithm catalogs (no network), use the exported constants:

import { CbteTipo, DocTipo, AlicuotaIva, Concepto } from "@ar-agents/facturacion";

CbteTipo.FACTURA_C       // 11
DocTipo.CUIT             // 80
AlicuotaIva.VEINTIUNO    // { id: 5, percent: 21 }
Concepto.SERVICIOS       // 2

Pre-flight validation

The library validates your SolicitarCaeInput LOCALLY before sending to AFIP, catching the most common rejection reasons:

• ImpTotal ≠ sum of components (AFIP error 10048)
• iva[].importe sum ≠ ImpIVA
• Factura C with ImpIVA > 0 (Monotributo can't discriminate IVA)
• Concepto = Servicios sin fchServDesde/Hasta/VtoPago
• Nota de Crédito/Débito sin cbtesAsoc
• Malformed cbteFch (must be YYYYMMDD)
• monId no-PES con monCotiz = 1
• cbteHasta < cbteDesde

import { validateSolicitarCae } from "@ar-agents/facturacion";

const v = validateSolicitarCae(input);
if (!v.valid) {
  // v.errors is an array of { field, message } in Spanish
  console.error(v.errors);
}

Saves you a network round-trip (and a CloudWatch entry) on every malformed request.

Robustez

The WsfeClient accepts requestTimeoutMs, maxRetries, and an onCall observability hook: all forwarded to both the WSAA token-refresh path and the per-comprobante WSFE path:

new WsfeClient({
  certPath: "...",
  keyPath: "...",
  cuit: "20417581015",
  env: "prod",
  requestTimeoutMs: 15_000,
  maxRetries: 2,
  onCall: (e) => metrics.histogram("wsfe.duration", e.durationMs, { label: e.label }),
});

License

MIT © Nazareno Clemente

Stability

This package is pre-1.0. Per npm convention, 0.x minor versions may include breaking changes. We document every breaking change in CHANGELOG.md under the corresponding minor bump and flag it explicitly. To avoid surprises:

# Pin to exact version (recommended for production):
pnpm add @ar-agents/<package>@<exact-version>

We commit to no breaking changes within a patch version, and we publish 1.0.0 once the public API has stabilized across at least two consecutive minor releases.