つみたて NISA シミュレーション

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

No annotations are provided. The description discloses that calculations use monthly compounding, which is a key behavioral trait. It does not mention side effects (likely none), permissions, or error handling. For a simulation tool, this is minimally adequate but lacks explicit safety/behavioral notes.

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 two sentences long, front-loaded with the core function. It is concise and free of unnecessary words. Could be slightly more compact by combining sentences, but overall efficient.

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 simple parameter set (3 required numbers) and the absence of an output schema, the description adequately conveys the inputs and the computed outputs (future value, profit, annual progression). It mentions monthly compounding, which is a critical detail. Most agents would be able to use this tool correctly.

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 has 100% description coverage, with each parameter already having clear schema descriptions (e.g., monthly contribution, annual rate as %). The tool description adds no additional semantic value beyond paraphrasing the parameters, meeting the baseline expectation.

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 that the tool estimates future value, profit, and annual progression using monthly compounding, with a specific verb (試算します) and resource (将来評価額・運用益・年次推移). It mentions NISA/iDeCo use case, but does not explicitly differentiate from sibling tools like calculate_compound_interest.

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 indicates the tool is for simple simulation of NISA/iDeCo, implying a target use case. However, it does not specify when to avoid using this tool or mention alternative tools (e.g., calculate_compound_interest for general scenarios).

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