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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds genuine value by disclosing the temporal dynamics: the answer grows with source data, and an absent name is absent today, not forever. This enriches the open-world semantics without contradicting the annotations.

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?

Extremely compact — three short sentences carrying the purpose, the usage trigger, and the behavioral caveat. Nothing is wasted, and the key question is front-loaded.

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?

With an output schema present, full parameter coverage, and annotations carrying the safety profile, the description is nearly complete for a simple listing tool. The only minor omission is explicit naming of what a 'fiscal kind' is, though sibling context makes it reasonably inferable.

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 description coverage is 100%, so the schema fully documents the 'country' parameter. The description adds no parameter-specific detail beyond what the schema already states, matching the baseline 3 for fully covered schemas.

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?

States a specific verb+resource ('list' classifications with 'data') scoped by country. The purpose is immediately clear and distinct from all siblings, which concern invoice operations, fiscal codes, and taxpayer lookups — none list fiscal classifications.

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?

'Ask this before assuming a classification exists' gives clear, actionable usage timing. However, it names no explicit alternatives and offers no when-not-to-use condition, so the guidance is context-rich but lacks exclusionary detail.

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