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

The annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context beyond that: it is a SN2025 reference lookup, accepts Norwegian or English words and code prefixes, and returns hierarchical codes where broader codes include all subclasses.

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 tight sentences with no wasted words. The core purpose is front-loaded, followed by the practical routing instruction and hierarchy caveat.

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 simple read-only reference lookup with annotations covering safety and no output schema, the description gives enough to call it correctly and use the result. It could be slightly more complete by sketching the return shape, such as a list of matching codes with labels, but the essential context is present.

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 0% for the single required query parameter, so the description must compensate. It does so by explaining that query accepts Norwegian or English words or a code prefix, which is meaningful guidance for forming valid inputs, though it omits details like case sensitivity or exact prefix format.

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 and resource ('Look up SN2025 industry codes') and immediately clarifies the acronym ('the Norwegian NACE standard the register uses'), so an agent knows exactly what this tool returns. It also distinguishes itself from company-focused siblings by routing the result into search_norwegian_companies.

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?

It explicitly tells the agent to use the retrieved codes in search_norwegian_companies and explains the hierarchy rule that a broader code such as 62 includes subclasses. What is missing is an explicit statement of when not to use this tool, such as when free-text company search is preferable.

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