個人資産形成プランナー（NISA / iDeCo）

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

No annotations are provided, so the description carries the full burden. It discloses that the tool runs three scenarios and auto-back-calculates, which indicates a safe, non-destructive calculation. However, it does not mention any data persistence, privacy, or rate limits, though these are less critical for a simulation tool.

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, fairly long sentence but is front-loaded with the core purpose and includes key details. It is clear and efficient, though breaking it into multiple sentences could improve readability.

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 description explains the main outputs (future assets, sufficiency under three scenarios, required monthly amount if shortfall) despite lacking an output schema. This covers the essential return values for a planning tool with 8 parameters.

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 100% with descriptions for all 8 parameters. The description adds value by explaining how risk tolerance maps to three scenarios and mentioning the auto back-calculation feature, which goes beyond the schema's per-parameter details.

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 estimates future assets and retirement fund sufficiency under three scenarios (optimistic/realistic/pessimistic) based on multiple inputs, and auto-calculates required monthly savings if insufficient. This distinguishes it from siblings like calculate_compound_interest or calculate_required_monthly, which are more specific.

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 usage for comprehensive retirement planning but does not explicitly specify when to use this tool versus alternatives like simulate_nisa or calculate_required_monthly. No when-not-to-use guidance is provided.

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