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

Annotations already declare readOnly/idempotent/openWorld, so safety is covered; the description goes further with the x402 payment model (0.01 USDC per successful call on Base, errors free) and the sole-proprietorship exclusion, both of which materially affect how an agent should budget and interpret calls. It stops short of rate limits or result-shape expectations.

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: capability, caveat, cost. The scoping facets come first, and the pricing sentence is short and decision-relevant. No filler.

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 7-parameter, no-required-argument search with full schema coverage and no output schema, the description covers scope, an important exclusion, and the payment model. Only pagination/result-volume expectations are left implicit, which the page/size parameters largely carry.

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 already explains each of the 7 parameters, including NACE format, municipality code format and defaults. The description adds one genuine semantic point (name searches never match sole proprietorships) but otherwise does not extend parameter meaning beyond the schema.

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 ('Search') and resource ('Norwegian legal entities') and enumerates the five queryable facets, which lets an agent distinguish it from search_finnish_companies and from get_company (single-entity lookup). The Norwegian scope is explicit, not inferred.

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?

Usage is implied by the facets and by the note that sole proprietorships are excluded from name searches, which is a real retrieval caveat. However, there is no explicit guidance on when to use this versus get_company for details or how to page through to a complete result set.

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