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

With annotations providing no safety hints, the description carries the burden and does disclose key behaviors: it creates an external document, uses statutory/commercial/custom rates, counts interest to today for unpaid invoices, and is exact to the grosz. It doesn't mention authentication or legal-effect caveats, but the core behavioral profile is transparent.

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?

Three sentences with no filler; the main action and output are front-loaded. Each sentence adds necessary context: calculation logic, rate sources, and behavior for unpaid invoices.

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?

The description sufficiently explains the tool's output and rate behavior, which is important because there is no output schema. It doesn't spell out required creditor/debtor/invoices fields, but the rich input schema covers that, and the brief output description is adequate for a no-output-schema tool.

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 100%, so the input schema already explains all 11 parameters. The description adds useful context around custom rates and unpaid-invoice interest counting, but it doesn't need to compensate for missing parameter documentation.

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 states a specific verb+resource: it calculates Polish late-payment interest, creates an interest note (nota odsetkowa), and returns a short link to the PDF. This clearly distinguishes it from the sibling calculate_late_payment_interest by emphasizing document creation and delivery.

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 implies usage for overdue Polish invoices and mentions rate options, but it never explicitly tells an agent when to choose this tool over calculate_late_payment_interest or when not to use it. The boundary between 'just calculate' and 'calculate and create a note' is left to inference.

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