# Tax Prep

> Quarterly tax preparation — Modelo 303 (IVA) and Modelo 130 (IRPF). Run at the end of each quarter. Reads GnuCash snapshot and Harvest invoice data, produces a clean summary for filing or gestora review.

- Skill: `markbaindesign/tax-prep` (Agent Skill)
- Install (CLI): `npx skillmds@latest add markbaindesign/tax-prep`
- Raw SKILL.md: https://api.skillmd.com/api/skills/markbaindesign/tax-prep/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Finance & Business
- Author: markbaindesign (https://skillmd.com/u/markbaindesign)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/markbaindesign/tax-prep

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# Tax Prep

Maintains the quarterly record required for Spanish autónomo tax filing. Never files — Mark reviews and files, or sends to the gestora.

## Steps

### 1. Identify the quarter

Accept a quarter argument (e.g. `Q1 2026` = Jan–Mar, `Q2 2026` = Apr–Jun). If not provided, infer from today's date.

### 2. Read financial data

Read `/media/data/Dropbox/Work/Admin/Financial/Accounting/accounts.json` (GnuCash snapshot). If more than 24 hours old, run `python3 studio/collectors/gnucash_collector.py` to refresh.

`accounts.json`'s `harvest.invoices` field only carries *open* (unpaid) invoices — not enough for accrual-basis tax prep, since a paid invoice from earlier in the quarter still counts as income the quarter it was issued (aletheia-codex.md §4). Pull the full set directly instead:

```bash
python3 - <<'PY'
import sys
from datetime import date
from dotenv import load_dotenv
import os
load_dotenv('/media/data/dev/bain-studio/studio/.env')
sys.path.insert(0, '/media/data/dev/bain-studio/studio/dashboard')
from harvest_client import HarvestClient

client = HarvestClient(os.environ['HARVEST_TOKEN'], os.environ['HARVEST_ACCOUNT_ID'])
invoices = client.get_invoices_in_range('{quarter_start}', '{quarter_end}')  # e.g. 2026-04-01, 2026-06-30
for inv in invoices:
    print(inv)
PY
```

Every invoice returned counts toward the quarter's income regardless of `state` (draft/open/paid/closed) — don't filter by state here.

### 3. Modelo 303 — IVA

For each invoice issued to a Spanish B2B client in the quarter:
- IVA devengado (collected): invoice base × 21%
- IVA soportado (deductible inputs): sum deductible business expenses × 21%
- IVA a ingresar = devengado − soportado

Produce the 303 summary table:

| Invoice | Client | Base | IVA 21% |
|---|---|---|---|

**Total IVA devengado:** €
**Total IVA soportado:** €
**IVA a ingresar / (a devolver):** €

Deadline: 20th of the month following the quarter end (e.g. Q1 → 20 April).

### 4. Modelo 130 — IRPF

For all professional income in the quarter (Spanish and international):
- Ingresos: sum of all invoices issued (base, pre-IVA)
- Gastos deducibles: sum of deductible expenses
- Rendimiento neto: ingresos − gastos
- Pago fraccionado: rendimiento neto × 20% (less any IRPF already withheld by Spanish clients)

Produce the 130 summary:

| Quarter | Ingresos | Gastos | Rendimiento | IRPF retenido | A ingresar |
|---|---|---|---|---|---|

Deadline: same as 303 — 20th of the month following quarter end.

### 5. Output

Save to `/media/data/Dropbox/Work/Admin/Financial/Accounting/tax-{YYYY}-Q{N}.md`. Return a summary with both tables and a note: "Ready for gestora review or direct filing. Deadline: {date}."

### Guard rails

- Never file. Never send to a third party. This skill produces the pack; Mark decides what to do with it.
- Spanish-specific: these models assume Spanish autónomo status. Flag if the situation is different.
- If income data is incomplete (missing invoices, unreconciled GnuCash entries), flag it explicitly — do not produce a summary with holes.