jp_ideco_tax_saving

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

With no annotations provided, the description bears full responsibility for behavioral disclosure. It mentions 'contributions are fully deductible' and limits to 'deduction effect only', but it does not state whether the tool returns a combined value or separate values for income and residence taxes, nor any contribution limits or calculation assumptions.

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 plus a short qualifier, communicating the core purpose without fluff. It is appropriately front-loaded and every word contributes value.

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?

The tool has no output schema or annotations, so the description must explain the return value and any assumptions. It fails to specify the output format (e.g., a single total vs. separate tax types) and does not mention contribution limits or tax bracket assumptions, making it incomplete for a calculation tool.

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 provides descriptions for both parameters, achieving 100% coverage. The description adds no additional parameter-level semantics, so it remains at the baseline of 3.

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 uses the specific verb 'Calculate' and identifies the resource 'iDeCo contributions', clearly stating the outcome as annual income-tax and residence-tax reduction. This distinguishes it from the sibling date tools and the furusato tax tool.

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 implies the tool is for calculating the tax savings from iDeCo contributions, and the phrase 'Deduction effect only' sets an exclusion boundary. However, it doesn't explicitly name alternative tools or provide clear when-to-use vs. not-use guidance.

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