finamt

English | German

An agentic Python library for extracting structured data from receipts and invoices and preparing essential German tax return statements.

Features

• German Tax Alignment — Category taxonomy and VAT handling aligned with German fiscal practice
• Local-First — Everything runs completely offline; models are auto-downloaded from HuggingFace and cached locally, data is stored in a local database
• 4-Agent Pipeline — Sequential specialised agents for metadata, counterparty, amounts, and line items; short focused prompts for reliable local model performance
• Web UI — Full browser interface for uploading, reviewing, editing, and managing receipts and invoices and preparing tax returns
• ELSTER submission — Annual Umsatzsteuererklärung (USt), E-Bilanz, and UStVA submitted directly to the Finanzamt via the official ERiC library; confirmed working end-to-end with a formal Finanzamt acknowledgement

Tech Stack

Backend

• Python — package language
• FastAPI — backend for the web UI
• PaddleOCR — OCR for scanned PDFs
• Tesseract — OCR for scanned PDFs and images when PaddleOCR fails or times out
• HuggingFace Hub — models downloaded and cached automatically on first use; no separate server required
  • Mistral – mistral:7b is the recommended default (maps to mlx-community/Mistral-7B-Instruct-v0.3-4bit on Apple Silicon)
  • Qwen – qwen2.5:7b-instruct-q4_K_M is a good alternative (maps to mlx-community/Qwen2.5-7B-Instruct-4bit on Apple Silicon)
  • mlx-lm — 4-bit inference on Apple Silicon (M-series) via the MLX framework; ~13 % faster than Ollama
  • transformers — cross-platform inference fallback (Linux / Windows / Intel Mac)
• SQLite – local database for original receipts and extracted data

Frontend

• React — interactive frontend
• Vite — fast dev server and production bundler
• Tailwind CSS — utility-first styling
• TypeScript — type-safe component and API code

CLI

• Typer — CLI with coloured progress output

Packaging

• PyPI — distributed as an installable Python package

Installation

pip install finamt

For CLI usage, installing via pipx is recommended — it places finamt into its own dedicated virtual environment, ensuring its dependencies never interfere with your other projects, while still exposing the finamt command globally without requiring you to activate a virtualenv:

pipx install finamt

Note for Python 3.14+ users: finamt currently requires Python 3.13. If your system Python is 3.14 or newer, install uv to manage Python versions and pass the resolved path to pipx:

uv python install 3.13
pipx install finamt --python $(uv python find 3.13)

System Requirements

• Python 3.10+
• Tesseract OCR (optional fallback when PaddleOCR times out)

No Ollama required. LLM models are downloaded automatically from HuggingFace on first use (~4 GB per model) and cached at ~/.cache/huggingface/hub. On Apple Silicon the mlx-lm backend is used; on other platforms transformers is used.

Tesseract OCR (optional fallback from PaddleOCR)

Ubuntu / Debian

sudo apt-get install tesseract-ocr tesseract-ocr-deu

macOS

brew install tesseract tesseract-lang

Windows

Download the installer from https://github.com/UB-Mannheim/tesseract/wiki and add it to your PATH.

Quick Start

Interactive UI

finamt serve

Interactive UI to upload receipts and manage tax statements

Python API

Process a single receipt (expense)

from finamt import FinanceAgent

agent = FinanceAgent()
result = agent.process_receipt("receipt.pdf")

if result.success:
    data = result.data
    print(f"Counterparty: {data.vendor}")
    print(f"Date:         {data.receipt_date}")
    print(f"Total:        {data.total_amount} EUR")
    print(f"VAT:          {data.vat_percentage}% ({data.vat_amount} EUR)")
    print(f"Net:          {data.net_amount} EUR")
    print(f"Category:     {data.category}")
    print(f"Items:        {len(data.items)}")

    # Serialise to JSON
    with open("extracted.json", "w", encoding="utf-8") as f:
        f.write(data.to_json())
else:
    print(f"Extraction failed: {result.error_message}")

Sale invoices (outgoing)

result = agent.process_receipt("invoice_to_client.pdf", receipt_type="sale")

Batch processing

from pathlib import Path
from finamt import FinanceAgent

agent = FinanceAgent()
results = agent.batch_process(list(Path("receipts/").glob("*.pdf")))

for path, result in results.items():
    if result.success:
        print(f"{path}: {result.data.total_amount} EUR")
    else:
        print(f"{path}: ERROR — {result.error_message}")

Configuration

Settings are read in priority order from: environment variables → .env file → built-in defaults.

# .env

# OCR and general settings
FINAMT_OCR_LANGUAGE=german
FINAMT_OCR_TIMEOUT=60
FINAMT_TESSERACT_CMD=tesseract
FINAMT_OCR_PREPROCESS=true
FINAMT_PDF_DPI=150

# Extraction agents — all 4 agents use this model
FINAMT_AGENT_MODEL=mistral:7b
FINAMT_AGENT_TIMEOUT=60
FINAMT_AGENT_NUM_CTX=4096
FINAMT_AGENT_MAX_RETRIES=2

You can also pass config objects directly:

from finamt import FinanceAgent
from finamt.agents.config import Config, AgentsConfig

agent = FinanceAgent(
    config=Config(ocr_language="deu+eng", pdf_dpi=150),
    agents_cfg=AgentsConfig(agent_model="mistral:7b"),
)

API Reference

FinanceAgent

class FinanceAgent:
    def __init__(
        self,
        config:     Config | None = None,
        db_path:    str | Path | None = "~/.finamt/default/finamt.db",
        agents_cfg: AgentsConfig | None = None,
    ) -> None: ...

    def process_receipt(
        self,
        pdf_path:     str | Path | bytes,
        receipt_type: str = "purchase",   # "purchase" or "sale"
    ) -> ExtractionResult: ...

    def batch_process(
        self,
        pdf_paths:    list[str | Path],
        receipt_type: str = "purchase",
    ) -> dict[str, ExtractionResult]: ...

ExtractionResult

Always check success before accessing data.

@dataclass
class ExtractionResult:
    success:         bool
    data:            ReceiptData | None
    error_message:   str | None
    duplicate:       bool                  # True if already in the database
    existing_id:     str | None            # ID of the original if duplicate
    processing_time: float | None          # seconds

    def to_dict(self) -> dict: ...

ReceiptData

@dataclass
class ReceiptData:
    id:               str                  # SHA-256 of OCR text — stable dedup key
    receipt_type:     ReceiptType          # "purchase" or "sale"
    counterparty:     Counterparty | None  # vendor (purchase) or client (sale)
    receipt_number:   str | None
    receipt_date:     datetime | None
    total_amount:     Decimal | None
    currency:         str | "EUR"
    vat_percentage:   Decimal | None       # e.g. Decimal("19.0")
    vat_amount:       Decimal | None
    net_amount:       Decimal | None       # computed: total - vat
    category:         ReceiptCategory
    items:            list[ReceiptItem]
    vat_splits:       list[dict]           # for mixed-rate invoices

    vendor: str | None                     # alias for counterparty.name

    def to_dict(self) -> dict: ...
    def to_json(self) -> str: ...

Counterparty

@dataclass
class Counterparty:
    id:          str           # UUID assigned by the database
    name:        str | None
    vat_id:      str | None    # EU format, e.g. DE123456789
    tax_number:  str | None    # German Steuernummer, e.g. 123/456/78901
    address:     Address
    verified:    bool          # manually confirmed in the UI

ReceiptItem

@dataclass
class ReceiptItem:
    position:    int | None
    description: str
    quantity:    Decimal | None
    unit_price:  Decimal | None
    total_price: Decimal | None
    vat_rate:    Decimal | None
    vat_amount:  Decimal | None
    category:    ReceiptCategory

    def to_dict(self) -> dict: ...

ReceiptCategory

A validated string subclass. Invalid values are silently normalised to "other".

from finamt.agents.prompts import RECEIPT_CATEGORIES   # list[str]
from finamt.models import ReceiptCategory

cat = ReceiptCategory("software")       # valid
cat = ReceiptCategory("unknown_value")  # normalised to "other"
cat = ReceiptCategory.other()           # explicit fallback

Exceptions

All exceptions inherit from FinanceAgentError.

Exception	Raised when
OCRProcessingError	PDF cannot be opened or text extraction fails
LLMExtractionError	Model returns invalid JSON after all retries
InvalidReceiptError	Extracted data fails business-logic validation

from finamt.exceptions import FinanceAgentError, OCRProcessingError

try:
    result = agent.process_receipt("scan.pdf")
except OCRProcessingError as e:
    print(e)

Extraction Pipeline

Each receipt goes through four sequential LLM calls, each with a short focused prompt:

Agent	Extracts
Agent 1	Receipt number, date, category
Agent 2	Counterparty name, VAT ID, Steuernummer, address
Agent 3	Total amount, VAT percentage, VAT amount
Agent 4	Line items (description, VAT rate, VAT amount, price)

Results are merged in Python — no additional LLM validation step. Debug output for every agent (prompt, raw response, parsed JSON) is saved to ~/.finamt/debug/<receipt_id>/.

Categories and Subcategories

Every receipt is tagged with a category and optional subcategory. Categories map directly to line items in the German ELSTER tax forms (EÜR / UStVA), so the correct totals land in the right fields without manual re-sorting.

Category	Subcategories
services	freelance consulting legal accounting notary
products	physical_goods digital_goods merchandise samples
material	consumables raw_materials packaging merchandise
equipment	low_value_asset computer machinery furniture tools
software	subscriptions pay_as_you_go licenses hosting domains
licensing	software_licenses media_licenses other_ip
telecommunication	phone internet bundled
travel	transport accommodation meals per_diem incidental
car	fuel parking garage repair maintenance insurance leasing rental
education	courses books conferences certifications
utilities	electricity heating water waste
insurance	liability health vehicle property
financial	bank_fees interest loan_costs payment_fees
office	rent coworking storage cleaning security
marketing	advertising print_media trade_fairs sponsorship gifts
donations	charitable political church
public_fees	broadcasting_fee ihk_hwk berufsgenossenschaft other_public_fee
other	membership_fees sundry

TODO

Receipt processing

• OCR pipeline (PaddleOCR + Tesseract fallback)
• 4-agent extraction (metadata, counterparty, amounts, line items)
• Deduplication, database storage, batch processing

Tax calculation

• UStVA — VAT pre-return (monthly / quarterly)
• UStE — annual VAT return
• EÜR — income-surplus statement
• KSt 1 — corporate income tax return
• GewSt — trade tax return
• Jahresabschluss — annual accounts (Bilanz + GuV, § 267a HGB)

Validation

• XSD validation of generated XBRL against HGB taxonomy
• ELSTER dry-run / test-server validation before live submission

ELSTER transmission

• UStVA — ELSTER XML builder + Kennzahlen mapper + RSA signing + HTTP submission
• E-Bilanz — XBRL instance document (HGB taxonomy v6, MicroBilG schema)
• E-Bilanz — ERiC ctypes bridge for actual transmission
• USt — ELSTER XML builder + ERiC ctypes submission (confirmed end-to-end)
• UStVA — ELSTER XML builder + ERiC ctypes submission (confirmed end-to-end)
• KSt — ELSTER XML builder
• GewSt — ELSTER XML builder
• EÜR, ESt — ELSTER XML builder

Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/my-change) and make your changes
3. Run the test suite:

   pytest --cov=src --cov-report=term-missing

4. Lint and format with Ruff:

   ruff check --fix src/ tests/
   ruff format src/ tests/

5. Update the documentation
6. Submit a pull request

License

AGPL-3.0 — see LICENSE for details.

Commercial Licensing

finamt is available under the AGPL-3.0 license.

If you wish to use finamt in a proprietary setting, without the obligations of the AGPL (e.g. without releasing source code or for use in a commercial SaaS product), a commercial license is available.

For inquiries, contact: info@spaceoctahedron.com

Third-Party Components and Models

This software depends on external libraries and services, including:

• PaddleOCR (Apache License 2.0)
• Tesseract OCR (Apache License 2.0)
• HuggingFace Hub / transformers (Apache License 2.0)
• mlx-lm (MIT License, Apple Silicon only)

finamt downloads language models from HuggingFace (e.g. Mistral, Qwen) on first use and caches them locally.

These models are not distributed with this software and are subject to their own licenses. Users are responsible for complying with the respective terms when downloading and using such models.

Disclaimer

This software is provided for informational and automation purposes only.

It does not constitute tax, legal, or accounting advice.

While finamt is designed to assist with the preparation of German tax-related data (e.g. VAT returns, EÜR, ELSTER submissions), no guarantee is made regarding:

• correctness of extracted data
• completeness of financial records
• compliance with applicable tax laws and regulations
• acceptance by tax authorities

Users are solely responsible for verifying all outputs before submission to any authority.

Always consult a qualified tax advisor (Steuerberater) for legally binding guidance.

To the maximum extent permitted by law, Space Octahedron GmbH assumes no liability for:

• errors in OCR or LLM-based extraction
• incorrect classifications or calculations
• rejected or incorrect tax filings
• financial losses or penalties arising from use of this software

Product Information (ELSTER)

• Produktname: Space Octahedron® finamt
• Hersteller: Space Octahedron GmbH
• Kontakt: info@spaceoctahedron.com