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

With no annotations provided, the description carries the full behavioral burden. It discloses the required authentication prerequisite (e-Stat application ID) and the metadata fields returned, which is useful context. It does not mention network failures, rate limits, or how the ID is supplied, but for a straightforward read-only search tool this is adequate.

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 a single sentence that front-loads the action and scope, then adds return details and the authentication requirement. Every phrase earns its place with no wasted words.

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 simple two-parameter tool with no output schema, the description covers the core call intent, returned fields, and a needed credential. It could add more about error behavior or how the application ID is passed, but the essential information is present.

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?

The input schema already documents both parameters with 100% coverage, so the description adds limited parameter-level meaning. 'By keyword' reiterates the keyword parameter but does not enrich it 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?

The description names a specific action ('Search'), a concrete resource ('Japanese official statistics tables (e-Stat)'), and the result shape ('English-keyed table metadata'). It is clearly distinct from the sibling tools, which target laws and corporations.

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?

The description makes the intended domain unambiguous by naming e-Stat as the source and states the key prerequisite of an application ID. It does not explicitly contrast with siblings, but the resource differences are obvious enough that an agent can choose correctly.

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