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

No annotations are present, so the description carries the full behavioral burden. It implies a safe read-only lookup and enumerates the data categories returned (status, incorporation date, address), which is useful. However, it does not disclose permissions, rate limits, error behavior, or whether results are cached, leaving meaningful gaps for a tool with zero annotation coverage.

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 sentences, each earning its place: capability, usage routing, and exclusions. The core capability is front-loaded before the guidance, and there is 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 two-parameter lookup with no output schema, the description tells the agent what the tool verifies and what categories of data it returns. It is nearly complete, though a brief note on expected response shape or failure modes would close the remaining gap.

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 both parameters are already fully documented in the input schema. The description restates what the parameters accept (registration number or VAT ID, jurisdiction) but adds no format constraints or syntax beyond the schema, making the baseline score of 3 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 names specific verbs and resources: official company registration lookup, EU VIES VAT validation, tax ID status, and registered legal address. It clearly distinguishes itself from getCorporateDirectorsUbo and checkCorporateInsolvency, so an agent can select it without ambiguity.

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 states when to use the tool (KYB verification on a legal entity's registration number, VAT ID validity, active/dissolved status, incorporation date, registered address) and when not to use it, naming the correct alternative sibling for each excluded case. This is a complete routing guide.

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