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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so the safety profile is covered. The description adds meaningful behavioral context: it explains the partial-match semantics of the 'name' parameter, warns that Latin-script queries match a sparse romanised field dominated by municipal bodies, and notes the response flags this situation. This is valuable beyond the annotations.

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 tight and well-structured: purpose first, then the list of searchable criteria, then the return fields. Every sentence carries information; there is no fluff or redundancy. It front-loads the core purpose before any details.

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 search tool with 13 optional parameters and no output schema, the description covers the essential search dimensions and the returned fields. Pagination is handled by schema descriptions. It does not mention rate limits or error behavior, but those are not critical for an agent to invoke the tool correctly, and the _apiKey parameter references quota. Overall, it is sufficiently complete for correct usage.

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 every parameter has its own description. The main description summarizes the key search dimensions but does not add new meaning beyond the schema. It correctly maps to the parameters but provides no extra syntax or edge-case guidance beyond what the schema already offers.

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 opens with a clear verb ('Find') and a specific resource (Japanese companies with 13-digit corporate numbers), and enumerates the search dimensions (name, prefecture, corporate form, capital, employee count, revenue, procurement, subsidies, patents, financials). This distinguishes it from sibling gbiz tools that focus on profiles, procurement, or subsidies.

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: you use this tool when you need to search for companies matching various criteria and get a list with basic facts. However, there is no explicit guidance on when to prefer this over siblings like gbiz_company_profile or gbiz_company_records, nor any 'when not to use' statement. The intent is inferable but not spelled out.

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