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

Beyond the read-only/open-world annotations, it discloses that the data is public open data, that financial/credit information is excluded, the exact per-call price, payment rails, and that failed calls are not charged. These are material behavioral details an agent needs before invoking a paid tool.

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?

The description is front-loaded with what the tool does, followed by scope limitations and pricing. It is compact and every sentence adds useful information.

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?

With only two parameters, full schema coverage, annotations, and an output schema, the description supplies the remaining essential context: data scope, exclusions, pricing, and payment behavior. Nothing critical is missing for correct invocation.

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 100%, so the query and limit parameters are already fully documented. The description adds only that searching is by company name, which is already covered by the schema; baseline 3 is appropriate.

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 uses a specific verb (searches) and resource (Finland YTJ business register / PRH open data), and it clearly scopes the result fields. The mention of Finland distinguishes it from the many other country-registry siblings.

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 gives clear context for use: searching Finnish companies by name, with an explicit exclusion that it does not provide financial or credit information. It does not name alternatives such as other Finnish or Nordic registries, so it falls short of full when-to-use/when-not guidance.

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