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

With no annotations at all, the description carries the full burden. It does add real value by naming the upstream registry, listing the returned attributes, and disclosing the $0.25 USDC cost — the latter is important for an agent deciding whether to call. However, it says nothing about authentication/payment mechanics, rate limits, pagination behavior, or what an empty result looks like.

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?

Dense and front-loaded: purpose, source, return fields, search keys, example, price — no filler sentences. The field enumeration is list-like but each token carries information; the only minor cost is that it crowds out explanation of q and limit.

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 tool with no annotations, no output schema, and 4 parameters at 0% schema coverage, the description does good work by substituting a field list for the missing output schema and flagging cost. It falls short on the two undocumented parameters and on failure/pagination behavior, which an agent needs before calling.

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%, so the description must compensate, and it only partially does: orgnr gets a format hint ('9 digits') and an example, and name is implicitly understood. The two other parameters, q and limit, are never mentioned or distinguished from name, leaving the agent to guess whether q is an alias for name and what limit controls.

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 and resource ('Norwegian company lookup') plus the authoritative source (Brønnøysundregistrene Enhetsregisteret), then enumerates the fields returned. The country qualifier cleanly separates it from siblings like uk_company, fr_company, au_company and company_full without needing to name them.

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 says how to search ('by orgnr (9 digits) or name') and gives a concrete example call, which implies usage. But there is no explicit when-to-use guidance versus company_full, company_research, kyb_report, or registry_batch, and no statement of what to do when a lookup returns nothing.

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