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

Annotations already establish readOnlyHint=true and openWorldHint=false, so safety and closed-world behavior are covered. The description adds useful provenance ('from the open index') and the neutrality constraint about ranking, but says nothing about result limits, pagination, or what happens with zero matches.

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 sentences, zero filler, with the primary return value and the domain scope front-loaded. The differentiator from business search is placed last as a compact qualifier.

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 low-risk read-only lookup with a fully documented two-parameter schema, the description is essentially sufficient: it names the source index and the returned artifact (links). It could note result volume or behavior when no match exists, but nothing critical for correct invocation is missing.

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% and both parameters are documented in the schema, including the enum of topics and the guidance to combine 'municipality' topic with the municipality field. The description adds no parameter-level meaning beyond that, so the baseline of 3 applies.

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?

Specific verb ('Returns links') plus concrete resource ('free public services in Norway'), with explicit scope: state agencies by topic and municipal websites. The closing clause ('never ranked against businesses') separates it cleanly from the find_business sibling.

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 'never ranked against businesses' line implies this tool is for public-sector lookups rather than business searches, giving some routing signal. However, there is no explicit when-to-use, no when-not-to-use, and no named alternative, so the agent must infer the boundary with find_business/check_business.

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