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

Annotations already declare readOnlyHint=true and destructiveHint=false, so no contradiction exists. The description adds useful behavioral context beyond those annotations: amounts are exclusive of VAT, before discounts, per establishment and for all establishments together, and each rate table is cited. This is meaningful for an agent interpreting results.

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?

The description is front-loaded with the core function and stays reasonably compact. The third sentence about calculating costs and savings is slightly redundant with the first, but it adds useful purpose context without becoming bloated.

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?

There is no output schema, so the description compensates by stating what the result includes: annual base rates, VAT exclusion, pre-discount amounts, per-establishment and aggregate figures, and tariff-table sources. It does not explain the behavior of optional parameters like wachtruimte_m2 or behandelruimtes, but the schema already describes their 'alleen bij een praktijk' constraint, so the overall package is sufficient.

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?

The input schema covers all six parameters with 100% description coverage, so the schema carries the parameter-documentation burden. The description adds context around outputs ('per vestiging en voor alle vestigingen samen') but does not deepen the meaning of individual parameters beyond what the schema already provides. Baseline 3 is appropriate.

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 ('Berekent') and a concrete resource: the annual base rates of Buma/Stemra and Sena for background music in Dutch business premises, using official 2026 tariffs. This clearly distinguishes it from sibling tools like check_licentieplicht (legal obligation) and muziekadvies_voor_zaak (advice), despite not naming them.

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 gives clear context: it is for calculating licensing costs, including savings with music not licensed by Buma/Stemra and Sena. However, it does not explicitly state when to use this tool instead of siblings such as pakketten_en_prijzen or vergelijk_opties, nor does it offer any exclusions or alternative routing.

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