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

With no annotations, the description carries the transparency burden. It states the tool is 'browser-based' and performs estimation (試算), implying an interactive simulation without side effects. However, it does not describe output format, user interaction, or limitations.

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, compact sentence that immediately conveys the tool's function. The parenthetical note adds useful context without redundancy.

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 browser-based tool, the description adequately states its purpose but lacks details on how the agent should invoke it or what the user will see. It does not explicitly say 'opens a web page' or 'displays results', though 'browser-based' hints at this.

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 schema has zero parameters, so the description's mention of PR option rate as the input adds meaningful context. It clarifies the key variable users will need to configure, which is essential for a simulation tool with no formal parameters.

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 states the tool calculates the effect of PR option rate on profit/loss and search ranking improvement, using a specific verb (試算) and resource. This distinguishes it from sibling calculators like yahoo-shopping-calculator or rakuten-coupon-simulator.

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?

No explicit guidance is given on when to use this tool versus alternatives. It does not mention alternative tools, prerequisites, or exclusions. The intended use is only implied by the name and description.

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