Tax Engine is a remote MCP server that gives an AI agent 14 tools, among them calc_flat_tax_settlement, calc_set_aside, check_flat_tax_eligibility. It answers at https://freelax.cz/api/mcp over streamable HTTP, and it listed its tools to an anonymous client, so no sign-in was needed for that. Our probes reached it 5 of 6 times since 10 September 2026; the last check, on 19 October 2026, succeeded.
Deterministic Czech OSVC tax tools for 2026: tax, insurance, deadlines, VAT and exchange rates.
Description as the publisher wrote it.
| Tool | What it does |
|---|---|
calc_flat_tax_settlement | Given the paušální daň band you paid and the actual annual income, computes whether you owe a doplatek (top-up), get a vratka (refund), or must exit the flat-tax regime (income above 2,000,000 CZK). Inputs: currentBand, actualAnnualIncome, monthsInRegime, isProjection, flatRatePercent |
calc_set_aside | How much of a monthly OSVČ income to set aside for Czech income tax, social and health insurance, and what remains safe to spend. Supports mixed §7 business + §9 rental income and the paušální daň (flat tax) regimes. Inputs: monthlyIncome, rentalMonthlyIncome, taxRegime, activityType, flatRatePercent, advanceExempt |
check_flat_tax_eligibility | Screens whether an OSVČ may enter or stay in the paušální daň (flat tax) regime: public health insurance participation (decisive for foreigners), VAT-payer status, income ceiling 2,000,000 CZK, side income and secondary activity. Returns re Inputs: annualIncome, citizenshipType, publicHealthStatus, isVATRegistered, activityType, rentalAnnualIncome |
check_io_trigger | Checks whether buying services from abroad (Google Ads, Meta, ChatGPT, hosting…) or selling services to EU businesses has made an OSVČ an identifikovaná osoba under § 6h/§ 6i ZDPH, with the 15-day registration deadline (§ 97) and fact-fresh Inputs: vatStatus, vatStatusConfirmedAt, foreignServicePurchase, foreignServicePurchaseConfirmedAt, purchaseDate, foreignSales |
check_thresholds | Checks an annual income against the four statutory thresholds: VAT registration 2,000,000 CZK, immediate VAT registration 2,536,500 CZK, the 23% higher tax bracket, and the paušální daň eligibility ceiling. Reports approaching (90%), exceed Inputs: annualIncome |
compare_regimes | Compares the standard OSVČ regime against paušální daň (flat tax) for a yearly income, including tax credits that would be lost with the flat tax (children, spouse), and recommends the cheaper regime. Inputs: annualIncome, flatRatePercent, isMarried, numberOfChildren, spouseIncomeUnderLimit, hasChildUnder3 |
compute_year | Computes a full Czech OSVČ tax year from personal facts: income tax with credits (children, spouse, deductions), social and health insurance, monthly set-aside, safe-to-spend, flat-tax band and regime-eligibility evaluation. All figures com Inputs: taxYear, monthlyBusinessIncome, annualBusinessIncome, rentalMonthlyIncome, taxRegime, targetRegime |
convert_eur_czk | Converts an EUR amount to CZK using the Czech National Bank daily exchange rate (the rate used for Czech tax purposes). Reports the rate, its publication date and whether a stale cached ČNB publication had to be used. Fails closed when no v Inputs: amountEur |
czech_working_days | Czech public holidays for a year (including movable Easter feasts) and, for a specific date, whether it is a working day and the next working day a statutory deadline would shift to. Inputs: year, date |
estimate_penalty | Estimates the Czech penalty/interest for a late payment or filing: repo rate + 8 p.p. for insurance and tax interest (3.5% H1 / 3.75% H2 2026), 3 grace days for tax payments, 200 CZK health aggregation floor and the 1,000 CZK tax non-assess Inputs: obligationType, owedAmount, daysOverdue, gracePeriodActive, dueDate |
get_filing_deadlines | Deadline for the Czech personal income tax return (DPFO) for a given tax year, per filing route: paper, self-filed electronic, or via tax advisor. Weekend and holiday shifts are applied. Inputs: taxYear, route |
get_flat_tax_band | Which paušální daň band (pásmo 1/2/3) an annual income falls into given the expense flat-rate, the current monthly payment for that band, and the next income threshold to watch. Inputs: annualIncome, flatRatePercent |
get_prehled_deadlines | Filing deadlines for the annual OSVČ Přehled o příjmech a výdajích for both social insurance (ČSSZ) and the health insurer, per tax-return filing route, plus the payment due date (8 calendar days after the filing deadline). Inputs: taxYear, route |
get_rule_source | For a Czech OSVČ tax topic, returns the governing rule with current values, primary-source citations (zákon, ČSSZ, VZP, Finanční správa) with verification dates, and related Freelax articles. Topics: pausalni_dan, identifikovana_osoba, dph_ Inputs: topic, locale |
Every block below points at https://freelax.cz/api/mcp. Pick your client and copy.
claude mcp add --transport http tax-engine https://freelax.cz/api/mcp
{
"mcpServers": {
"tax-engine": {
"command": "npx",
"args": ["-y", "mcp-remote", "https://freelax.cz/api/mcp"]
}
}
}{
"mcpServers": {
"tax-engine": {
"url": "https://freelax.cz/api/mcp"
}
}
}{
"servers": {
"tax-engine": {
"type": "http",
"url": "https://freelax.cz/api/mcp"
}
}
}{
"context_servers": {
"tax-engine": {
"url": "https://freelax.cz/api/mcp"
}
}
}{
"mcpServers": {
"tax-engine": {
"serverUrl": "https://freelax.cz/api/mcp"
}
}
}{
"mcpServers": {
"tax-engine": {
"url": "https://freelax.cz/api/mcp"
}
}
}name: Tax Engine
version: 0.0.1
schema: v1
mcpServers:
- name: Tax Engine
type: streamable-http
url: https://freelax.cz/api/mcp{
"mcpServers": {
"tax-engine": {
"httpUrl": "https://freelax.cz/api/mcp"
}
}
}{
"mcpServers": {
"tax-engine": {
"type": "http",
"url": "https://freelax.cz/api/mcp"
}
}
}{
"mcpServers": {
"tax-engine": {
"url": "https://freelax.cz/api/mcp"
}
}
}goose://extension?url=https%3A%2F%2Ffreelax.cz%2Fapi%2Fmcp&type=streamable_http&id=tax-engine&name=Tax%20Engine
It answered our last check on 19 October 2026 in 148 ms. Over 6 checks since 10 September 2026 it answered 5. Status here comes from Neuronto's own probes, not from the publisher.
Yes. It is published by freelax.cz and served from freelax.cz, the vendor's own domain: https://freelax.cz/api/mcp.
14, as returned by the server's own tools/list on 11 September 2026: calc_flat_tax_settlement, calc_set_aside, check_flat_tax_eligibility, check_io_trigger, check_thresholds, compare_regimes, compute_year, convert_eur_czk, and 6 more.
It answered our last check on 19 October 2026 in 148 ms. Over 6 checks since 10 September 2026 it answered 5.
Put the server under mcpServers in ~/.cursor/mcp.json with the URL https://freelax.cz/api/mcp. The exact JSON is above, with the same setup for Claude Code, Claude Desktop, VS Code, Windsurf, Zed, Gemini CLI and the rest.
It listed its tools to an anonymous client, so reading the tool list needs no key. Individual tools can still ask for credentials in their own inputs.
Publisher: cz.freelax. Endpoint host: freelax.cz. ARD identifier: urn:air:cz.freelax:mcp:tax-engine.
First indexed 10 September 2026. The tools are exactly what the server returned; nothing on this page
is inferred from its name. Ranking in Neuronto search is never for sale.