The bridge lets your AI agent read Ukraine's tax e-cabinet (Електронний кабінет ДПС): debt and
overpayments, settlements with the budget, filed returns and their receipts, letters from the tax office. It runs on
your own computer. The key and its password go only into IIT's official signing widget, and the model gets only
allowlisted fields.
The e-cabinet has an official API for its private part. Each request carries a qualified electronic
signature (КЕП) over the taxpayer's number, so whoever holds a fresh signature can read the cabinet. The bridge is the
careful way to give that to an agent.
Demo: sole proprietor Olena Zrazok
The taxpayer is made up: single tax, group 3, 5%, Poltava. The tool results come from the bridge's own
code run on made-up cabinet answers, so they are exactly what a model would get; they stay in Ukrainian, as the
model reads them. The agent's replies are carried over from real sessions. Demo data.
What the cabinet returns and what the model sees
The cabinet returns the whole taxpayer card: tax number, address, phone, account numbers. The
bridge passes to the model only the fields we reviewed and allowed, and counts the rest, so the model knows something
was withheld. It sees an account number only by its last four digits.
the cabinet gave the bridge
the model got
Struck through: what the model never got. The account number (in amber) it sees only by its last
four digits. The cabinet's field labels are left out here for brevity.
How it works
The agent calls the bridge, which answers with a link to an unlock page and a pairing code.
You open the link in your own browser, check the code and sign in the IIT widget with a key file, a token or a
cloud key such as SmartID.
The widget signs only your tax number, or the organisation's code for a director's key. For 30 minutes that
signature lets the bridge read the cabinet.
Every answer from the cabinet goes through a field allowlist, and a log on your disk records every request.
What the bridge does not do
It never sees the key or the password: only IIT's widget takes them.
It signs and files nothing. It only reads.
It does not show the model the tax number, address, phone, account numbers or other people's names.
It does not keep a signature for more than 30 minutes and forgets it as soon as the client closes.
It lets no other person into the cabinet: the bridge is bound to whoever signed first.
Whatever the model sees, its provider sees too. The bridge narrows that to what an answer needs; it cannot
remove it.
Who it is for
Ukrainian sole proprietors (ФОП) who already ask AI about taxes, and heads of companies and
NGOs: a director's key opens the organisation's cabinet. Several taxpayers in one session, for accountants, is in
progress.
Tested in Claude Code on macOS. Codex, OpenCode, Hermes, Windows and Linux are next.
Beta
For now I set the bridge up by hand. Write which agent you use and I will send instructions.
The tax bridge shows the approach: data AI cannot reach on its own, and access you can trust.
I build the same for businesses. An agent reads your Excel price list, your books, CRM or a studio-built site under
the same rules: only the fields it needs, a log, and access that expires by itself.
---title: An AI bridge to Ukraine's tax e-cabinet
lang: en
site: NAVISTRI
---# Your tax cabinet, in a conversation with AI
The bridge lets your AI agent read Ukraine's tax e-cabinet (Електронний кабінет ДПС): debt and
overpayments, settlements with the budget, filed returns and their receipts, letters from the tax
office. It runs on your own computer. The key and its password go only into IIT's official signing
widget, and the model gets only allowlisted fields.
The e-cabinet has an official API for its private part. Each request carries a qualified electronic
signature (КЕП) over the taxpayer's number, so whoever holds a fresh signature can read the
cabinet. The bridge is the careful way to give that to an agent.
<!-- the state opened an API, AI became its client, the bridge only joined the two. --><!-- taxi = tax + AI: a ride to the cabinet that waits outside for 30 minutes. -->## Demo: sole proprietor Olena Zrazok
The taxpayer is made up: single tax, group 3, 5%, Poltava. The tool results come from the bridge's
own code run on made-up cabinet answers, so they are exactly what a model would get; they stay in
Ukrainian, as the model reads them. The agent's replies are carried over from real sessions.
[Demo data](/data/demo.en.json).
- How much do I owe the tax office?
- Was my nine-month return accepted?
- Any new letters from the tax office?
- Where do I pay the single tax?
- What does the model see about me?
## What the cabinet returns and what the model sees
The cabinet returns the whole taxpayer card: tax number, address, phone, account numbers. The bridge
passes to the model only the fields we reviewed and allowed, and counts the rest, so the model knows
something was withheld. It sees an account number only by its last four digits.
## How it works
1. The agent calls the bridge, which answers with a link to an unlock page and a pairing code.
2. You open the link in your own browser, check the code and sign in the IIT widget with a key file,
a token or a cloud key such as SmartID.
3. The widget signs only your tax number, or the organisation's code for a director's key. For 30
minutes that signature lets the bridge read the cabinet.
4. Every answer from the cabinet goes through a field allowlist, and a log on your disk records every
request.
## What the bridge does not do
- It never sees the key or the password: only IIT's widget takes them.
- It signs and files nothing. It only reads.
- It does not show the model the tax number, address, phone, account numbers or other people's names.
- It does not keep a signature for more than 30 minutes and forgets it as soon as the client closes.
- It lets no other person into the cabinet: the bridge is bound to whoever signed first.
Whatever the model sees, its provider sees too. The bridge narrows that to what an answer needs; it
cannot remove it.
## Who it is for
Ukrainian sole proprietors (ФОП) who already ask AI about taxes, and heads of companies and NGOs: a
director's key opens the organisation's cabinet. Several taxpayers in one session, for accountants, is
in progress.
Tested in Claude Code on macOS. Codex, OpenCode, Hermes, Windows and Linux are next.
## Beta
For now I set the bridge up by hand. Write which agent you use and I will send instructions:
[max@sushch.uk](mailto:max@sushch.uk?subject=DPS%20bridge%3A%20beta).
## The same bridge to your data
The tax bridge shows the approach: data AI cannot reach on its own, and access you can trust. I build
the same for businesses. An agent reads your Excel price list, your books, CRM or a studio-built site
under the same rules: only the fields it needs, a log, and access that expires by itself.
[Write to me](mailto:max@sushch.uk?subject=A%20bridge%20to%20our%20data).
<!-- the tax office holds the data, the model holds the attention, the bridge holds a key for 30 minutes. -->---
A NAVISTRI demo. Not a service of the State Tax Service (ДПС) or of IIT: the bridge uses the
e-cabinet's open API and IIT's official signing widget. Not tax advice. Built by
[Maksym Sushchuk](https://sushch.uk/).