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

With no annotations provided, the description must disclose behavioral traits. It does mention the cost ($0.03/site), which is a key operational detail. However, it does not disclose deeper behaviors like payment flow, error handling, or rate limits. The schema partially covers payment via the x_payment description, but the description itself adds only the cost.

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 packs the core purpose, output fields, and cost with no unnecessary words. It is front-loaded and easy to parse, earning a perfect score for conciseness.

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?

Given the absence of an output schema and annotations, the description should provide a fuller picture. It does list the output fields, which helps, and it mentions cost. However, it does not describe the payment process (covered in schema), failure modes, or any limitations. For a tool with only one required parameter and a straightforward output, this is adequate but not thorough, so a score of 3 is appropriate.

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 50% (only x_payment has a description). The description compensates somewhat by implying that the `url` parameter should be a Japanese company site, adding meaning beyond the bare schema. However, it does not elaborate on URL format or other possible parameters. For x_payment, the schema already provides full semantics, so the description adds no value there.

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 clearly identifies the resource (Japanese company site) and the output (standard profile JSON with specific fields like name, address, representative, capital, contact). However, the verb is implied rather than explicit (e.g., 'extract' or 'convert'), preventing a perfect score. The cost mention adds context but does not replace a clear action.

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 clearly implies when to use the tool: given a Japanese company website URL, you get a structured profile JSON. It does not explicitly exclude alternatives or mention siblings, but the context is unambiguous enough for an agent to select this tool for this specific task. Lack of exclusions prevents a score of 5.

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