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tax engine

cz.freelax/tax-engine

Deterministic Czech OSVC tax tools for 2026: tax, insurance, deadlines, VAT and exchange rates.

— the operator's own registry description reported

Publisher cz.freelax · first seen 2026-08-12 · endpoint https://freelax.cz/api/mcp

allow
verdict
mid-slow-solo
cluster
ok_tools
answers
14
tools served

Dependency rating derived

allow
allow — alive & usable · retrieval-public ● · V3 has answer key ◐
allow — because answers ●, 14 tools legible (band B) ●, no confirmed drift in 2 probes ●; not yet checked: truth (1 attempts unverifiable, 0 disagreements)

Cluster mid-slow-solo · distinctiveness 0.31 (typical). Every figure is a percentile or class within the 11,094-server censussee the whole spectrum.

Does it answer? Q1 · observed
answersalive_tools
latency551 ms
vs populationslow
protocolcurrent
authopen
Can it be used? Q4 · observed
tools14
vs populationmid
capabilities1
harnessB
Did it hold when checked? Q3–Q4 · derived
identitysolo
servers on its host1
verifiabilityunassessed
duplicate inventoryno
drift events0
answers true0/0 agree

🔏 Signed receipt rr_3ca78452a2c253168867a344 · ed25519 · key rs-rcpt-2026-08 — this rating is tamper-evident; an agent gets the full signature from check_server and can verify it against the published key.

Q1Does it answer?alive & usable — 2 probes ●evidence ↓
Q2What is it?retrieval-public ● evidence ↓
Q3Can it be checked?V3 has answer key ◐evidence ↓
Q4Did it hold?harness B · truth not yet run · no drift ●evidence ↓
Q5What company does it keep?mid-slow-solo · 1 on its host (context, not verdict) ◐evidence ↓

● observed · ◐ derived · ○ reported — the verdict synthesizes Q1–Q4; Q5 is context. Methodology →

History observed

Every probe we made, oldest → newest (2 shown, 2026-08-12 → 2026-08-14). Green answered · amber answered-but-walled · red no useful answer. A gap in our cadence is a gap in coverage, not evidence about the server.

changelog (1 events)
datetypewhat changed
2026-08-12outcomefirst probe: ok_tools

What kind of tools these are derived

Verification only means something relative to a tool's NATURE — an email-sender has no "true answer", a generator has no answer key. Classification evidence: classified from tool names/descriptions/annotations WE OBSERVED. What checking applies to each kind (the full methodology →):

naturetoolsmeaning what checking applies
retrieval-public12serves public factstruth-checkable against a public source — the V-ladder applies in full
computational2deterministic transformsself-checkable by re-computation and known-answer tests

Tools last seen observed

calc_flat_tax_settlement calc_set_aside check_flat_tax_eligibility check_io_trigger check_thresholds compare_regimes compute_year convert_eur_czk czech_working_days estimate_penalty get_filing_deadlines get_flat_tax_band get_prehled_deadlines get_rule_source

Harness readiness observed

Can an agent's harness pick this tool and call it correctly? Graded on the three things an agent reads — name, description, typed parameters. Band B — usable, with rough edges.

legibility checktools passingok
name is clear & specific14/14
has a description14/14
description is substantive14/14
parameters are typed14/14
parameters are described2/142/14

14 of 14 tools graded · 14 with a captured input schema. RS-008, Tier-1 — no domain knowledge, applies to any tool. “Alive” is not the same as “usable”.

Truth checks observed

Not yet confirmed — 1 attempt(s) currently unverifiable (rate limits, walls, or unmappable schemas — never counted against the server) · 0 disagreements.

claim classkeyverdictprimary source
fx-ratesEURUSDunverifiableecb-fx

Protocol conformance observed

2025-06-18
protocol version
session model
1.0.0
server version freelax-tax-engine

Capabilities: tools

Drift observed

No confirmed drift on record. Baseline set 2026-08-14; changes appear here after human review.

raw probe records
probed (UTC) outcomehttpmsprotocol
2026-08-14T19:58:40Zok_tools2005512025-06-18
2026-08-12T05:33:54Zok_tools2007792025-06-18

Watch or embed this verdict

verdict badge

Operators: put the live verdict in your README — it updates with every census, links back here, and is a dated observation, never a warranty:

[![Robin Saige verdict](https://robinsaige.com/badge/cz.freelax/tax-engine.svg)](https://robinsaige.com/s/cz.freelax/tax-engine)

Depend on it? Subscribe to its change feed — outcome changes and confirmed drift, no account needed. Building on it? The full dossier as JSON — verdict, rating, truth checks, history — stable enough to gate CI on.

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