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

Annotations already declare readOnly and idempotent, so the safety profile is covered. The description adds genuinely useful behavioral context: the tool is 'an indication only' and national law plus the member state's list are the final determiners, warning the agent not to treat the output as authoritative.

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 tight sentences with no filler. The main capability statement and the limitation caveat are both present, though leading with usage examples rather than the core purpose delays the essential information slightly.

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 9-parameter classification tool with no output schema, the description indicates what is returned (applicability plus category) and flags the important legal limitation. Combined with the well-described schema, an agent has what it needs to call it and interpret results.

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 67%, and the description references the applicable legal basis (Arts. 2 and 3, size rule of Recommendation 2003/361/EC), which helps the agent understand why sector, size and type matter. However, it adds little concrete meaning beyond what the schema's own field descriptions already provide.

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 outcome: indicates whether the NIS2 Directive applies to an organisation and classifies it as essential or important, derived from sector, size and type. This is clearly distinct from siblings like nis2_gap_assessment or reporting_deadlines, so an agent can route correctly.

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?

Gives concrete example user phrasings ('does NIS2 apply to my company?', 'are we an essential or important entity?') that map directly to invocation contexts. It lacks explicit when-not guidance or named alternatives, but the trigger conditions are clear.

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