Agentovka

Agentic access to Czech datové schránky (ISDS) via MCP.

Agentovka is an MCP server that lets AI agents (Claude Desktop, Claude Code, any MCP client) work with a Czech datová schránka through the official ISDS application interface - safely and with the legal semantics of the system treated as a first-class concern.

Not a thin SOAP wrapper. ISDS has legal semantics that a naive client silently violates. Reading your inbox legally delivers your mail and starts statutory deadlines; messages are permanently deleted after 90 days; sending a message is a legal act. Agentovka encodes these facts into the tools themselves. See docs/delivery-semantics.md - the heart of the project.

License: MIT · Python ≥ 3.11

---

Why this exists

The ISDS application interface (SOAP web services) may be used by any box owner with their login credentials, without prior registration. But the API mirrors the legal machinery of the system, and an agent that treats a datová schránka like an IMAP inbox will cause real legal consequences:

1. Reading triggers delivery. Listing received messages - whether by logging in or via the API (delivery event EV13) - marks all messages in the box as legally delivered (doručeno) and starts statutory deadlines (appeals, etc.). There is no consequence-free "peek".
2. Fiction of delivery. If nobody logs in, a message is deemed delivered on the 10th day after it was made available (§ 17 (4) of Act No. 300/2008 Coll.). If that day is a weekend or public holiday, delivery falls on the next working day.
3. 90-day deletion. Messages are permanently deleted 90 days after delivery. The Portál občana auto-archiving notably fails for messages delivered by fiction - a real gap that Agentovka's local archive closes.
4. Sending is a legal act (a submission to a public authority, a private-law act).

Agentovka's value is exactly this: a safety model and legal-semantics layer on top of a clean, reusable client.

Architecture

Two independent layers in one repository:

Layer	Package	What it is
Client library	isds_client	Pure Python client over the ISDS SOAP interface (via zeep, HTTP Basic auth over TLS). Typed pydantic models, a ZFO/CMS parser, and a small CLI. Usable standalone, without MCP.
MCP server	agentovka_mcp	A thin MCP layer over the library, using the official MCP Python SDK (FastMCP), stdio transport. Implements the safety model and the local archive.

The safety model

Tools are split into three classes, reflected in their names, descriptions and MCP annotations:

Class A - safe, no legal consequences (readOnlyHint)

• search_databox(query) - find a recipient's box (ID, name, type).
• get_databox_info() - info about your own box.
• list_archived_messages(), read_archived_message(id), search_archive(q) - read from the local archive only (no ISDS call).
• list_sent_messages(), get_delivery_receipt(id) - sent messages and their delivery receipts. These do not touch the received store and so do not trigger delivery (see delivery-semantics).
• get_delivery_deadline(delivery_date) - computes the fiction-of-delivery date (D+10, shifted to the next working day) using Czech public holidays.

Class B - triggers delivery (event EV13)

• list_received_messages(...), download_message(id).
• Each requires a mandatory acknowledge_delivery_trigger: bool. Without true the tool returns an error explaining the legal consequences instead of acting.
• download_message fetches the signed message (ZFO), stores it in the local archive, extracts attachments (the ZFO is a PKCS#7/CMS envelope), and returns metadata plus text content.

Class C - legal act: sending (destructiveHint)

• send_message(recipient_id, subject, attachments, dry_run=true).
• Defaults to dry_run=true (returns a preview). Actually sending requires dry_run=false and AGENTOVKA_ALLOW_SEND=true in the environment.

The server never polls the mailbox on its own - no background jobs, no scheduler. Every ISDS call happens only in response to an explicit tool call.

Installation & configuration

Run with uv:

uvx agentovka        # once published to PyPI
# or from a clone:
uv run agentovka

All configuration is via environment variables - credentials are never accepted as tool parameters (they would leak into the LLM context):

ISDS_USERNAME=...
ISDS_PASSWORD=...
ISDS_ENV=test                 # test | production  (default: test)
AGENTOVKA_ARCHIVE_DIR=~/.agentovka/archive
AGENTOVKA_ALLOW_SEND=false    # default: sending disabled

ISDS_ENV=test is the default on purpose - nobody should accidentally deliver their production mail while trying the server out. The test environment is free: create a test box at datovka-test.gov.cz (SOAP host ws1.czebox.cz).

Claude Desktop / Claude Code

Add to your MCP client config (e.g. claude_desktop_config.json):

{
  "mcpServers": {
    "agentovka": {
      "command": "uvx",
      "args": ["agentovka"],
      "env": {
        "ISDS_USERNAME": "your-test-username",
        "ISDS_PASSWORD": "your-test-password",
        "ISDS_ENV": "test",
        "AGENTOVKA_ALLOW_SEND": "false"
      }
    }
  }
}

See examples/ for ready-to-copy configs.

Using the library standalone

from isds_client import IsdsClient, IsdsEnvironment

client = IsdsClient(username="...", password="...", environment=IsdsEnvironment.TEST)
print(client.get_owner_info())

# Parse a ZFO file with no network access:
from isds_client.zfo import parse_zfo
parsed = parse_zfo(open("message.zfo", "rb").read())
print(parsed.envelope, parsed.files)

CLI:

isds-client owner-info
isds-client find "Ministerstvo vnitra"
isds-client parse message.zfo         # offline

Development

uv sync --group dev
uv run pytest            # unit tests (mocked SOAP)
uv run ruff check .
uv run mypy

# integration tests against the TEST environment (opt-in):
AGENTOVKA_RUN_INTEGRATION=1 ISDS_USERNAME=... ISDS_PASSWORD=... uv run pytest -m integration

See CONTRIBUTING.md.

Prior art & credits

• WSDL/XSD schema files are the ISDS interface descriptions distributed by CZ.NIC's dslib (LGPL).
• ZFO/CMS handling follows the approach of the maintained reference implementations libdatovka and the Datovka desktop app (CZ.NIC), and clean Python references such as isds-unpack.

---

⚠️ Disclaimer

Agentovka is an independent open-source project. The name Agentovka is a play on datovka (datová schránka): an agent's datovka.

This project is not a legal service. The information about delivery, fiction of delivery, deadlines and archiving is provided for engineering context and may be simplified or become outdated. It is not legal advice. For binding information consult the ISDS operating rules (Provozní řád ISDS), the relevant statutes, or a qualified lawyer.

Use against the test environment until you understand the legal consequences of each tool. You are responsible for what you send and for the deadlines that your reads set in motion.

---

Česky

Agentovka je MCP server, který umožní AI agentům (Claude Desktop, Claude Code, libovolný MCP klient) pracovat s českou datovou schránkou přes oficiální aplikační rozhraní ISDS - bezpečně a s ohledem na právní sémantiku systému.

Proč to není jen tenký SOAP wrapper

ISDS má právní sémantiku, kterou naivní klient tiše porušuje:

1. Čtení spouští doručení. Načtení seznamu dodaných zpráv (přihlášením i přes API - doručenkový kód EV13) způsobí, že se všechny dodané zprávy považují za doručené a začnou běžet zákonné lhůty. „Peek" bez následků neexistuje.
2. Fikce doručení. Nepřihlásí-li se nikdo, je zpráva doručena 10. dnem od dodání (§ 17 odst. 4 zák. č. 300/2008 Sb.); padne-li 10. den na víkend/svátek, nastává fikce nejbližší pracovní den.
3. Mazání po 90 dnech. Zprávy se 90 dní po doručení trvale mažou. Automatická archivace Portálu občana navíc nezvládá zprávy doručené fikcí - tuto díru řeší lokální archiv Agentovky.
4. Odeslání je právní úkon.

Podrobně a se zdroji: docs/delivery-semantics.md.

Bezpečnostní model

• Třída A (bezpečné): search_databox, get_databox_info, čtení lokálního archivu, list_sent_messages, get_delivery_receipt, get_delivery_deadline.
• Třída B (spouští doručení, EV13): list_received_messages, download_message - vyžadují parametr acknowledge_delivery_trigger=true, bez něj vrátí chybu s vysvětlením právních následků.
• Třída C (právní úkon): send_message - výchozí dry_run=true; skutečné odeslání vyžaduje dry_run=false a AGENTOVKA_ALLOW_SEND=true.

Server se nikdy sám od sebe nedotazuje schránky. Vše jen na explicitní volání nástroje.

Konfigurace

Výhradně přes proměnné prostředí (přihlašovací údaje nikdy neprotékají do LLM kontextu jako parametry nástrojů). Výchozí ISDS_ENV=test je záměrný bezpečnostní prvek. Testovací schránku zdarma získáte na datovka-test.gov.cz.

Upozornění

Agentovka je nezávislý open-source projekt. Název je odvozenina slova datovka. Projekt není právní služba - uvedené informace nejsou právní radou.