α
Multichannel intake
Documents arrive via WhatsApp, e-mail, API or the web portal. No human intervention, day and night.
channel.{whatsapp|email|api|web}
TITLE / 02
You send a PDF.
Nexa handles the rest
ABSTRACT
SUMMARY — Platform for the automation of document
management at companies and accounting practices: capture,
machine reading, fiscal validation, and ERP synchronisation —
with full traceability and human review whenever required.
FIG. 03 — CAPABILITIES
§ 1.2
Eight capabilities / none optional
Each item is documented in the in-app technical manual. Greek letters tag the source modules.
β
ML reading
GPT-4o with nine specialised prompts per document type. For e-invoice (FacturaE & UBL) we use a deterministic parser — AI is bypassed where unnecessary.
ocr.openai · facturae · ubl
γ
Fiscal validation
Arithmetic, VAT lines, NIF, IGIC, ISP, REAV, RE, DUA — all before touching the ERP. A detected error triggers re-processing automatically.
fiscal_validator.run(doc)
δ
Auto-reprocessing
If validation flags an inconsistency, a second LLM call with a case-specific prompt corrects the error (D1–D7, A1–A4, B1–B4, G1, G3).
reprocessor.case_{D1..D7}
ε
Idempotent sync
Connectors for Odoo, FacturaScripts and SAGE 200. Never duplicates a supplier, an invoice, or a journal entry.
sync_jobs.upsert(...)
ζ
Auditable trail
Every document carries a complete trail: who, what, when and with what confidence. Human review is recorded.
audit.trail(document_id)
η
Multi-tenant by default
Built for gestories. Each client sees only their own data; the manager has the global view across the portfolio.
tenant.scope(user)
θ
Confidence threshold
Below 0.80 → automatic human review. Above → direct sync. The threshold is your call.
if conf < 0.80 → review
Fifteen regimes
/ single pass
Nexa classifies the transaction type and applies the correct VAT regime automatically. Special cases (IGIC, REAV, margins) always flow through human review — they have too many subtleties to trust to a model alone.
▮ special.cases ⇒ human.review
| CODE | REGIME | DETAIL |
|---|---|---|
| domestic_vat | IVA general | 21% / 10% / 4% |
| domestic_exempt | Exempt operations | ensenyament, sanitat… |
| domestic_reverse_charge | Inversió subjecte passiu | art. 84.1.2 |
| isp_domestic | ISP — construction / chatarra | art. 84.1.2.f |
| eu_goods_acquisition | Intra-EU goods acquisition | M-303 + M-349 |
| eu_services_reverse_charge | Intra-EU services ISP | M-303 + M-349 |
| non_eu_oss | OSS — extracomunitari | B2C EU sales |
| import_goods_dua | Import with DUA | customs · supported VAT |
| canary_igic | IGIC canari | non-deductible mainland |
| reav_margin | REAV — travel agency | margin |
| special_vat_regime | Special regime (used goods) | margin |
| canary_ceuta_melilla | Ceuta / Melilla / Canàries | non-subject |
| three additional regimes documented in the technical manual. | ||
PL. VI — CONCLUSION
§ 1.4
See it run on your invoices,
not somebody else's.
Thirty minutes. We process samples from your sector live and tell you, plainly, where the model gets it right and where it doesn't.