Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The readOnlyHint annotation already covers safety. The description adds behavioral context by stating it returns 'reasons with severity' and specifies the screening dimensions (health insurance, VAT, income ceiling, side income). This goes beyond the annotation and provides useful expectations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two front-loaded sentences: the first states the purpose and key criteria, the second states the return format. Every word contributes value; no filler or repetition.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 6-parameter tool with no output schema, the description gives a strong overview of the logic and return structure. It could be more explicit about how parameters interact (e.g., rental income vs. main income) and the severity levels, but overall it satisfies the core need.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 50%, so the description compensates by naming the income ceiling (2,000,000 CZK), VAT-payer status, public health insurance participation, and side/secondary activity. This clarifies the meaning of annualIncome, isVATRegistered, citizenshipType, and activityType. However, rentalAnnualIncome is not explicitly mapped.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description uses a specific verb ('Screens whether') with a named resource ('OSVČ may enter or stay in the paušální daň regime') and lists the key criteria. This clearly distinguishes it from sibling tools like calc_flat_tax_settlement or check_thresholds.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description clearly implies when to use this tool (when checking flat tax eligibility) but does not explicitly mention alternatives or exclusions. It lacks guidance such as 'use check_thresholds for general thresholds' or 'use calc_flat_tax_settlement for calculations'.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.