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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds value beyond that by enumerating the computed metrics (NOI, debt service, after-tax cash flow, DSCR, IRR, equity multiple, sensitivity), which helps the agent understand the output composition. It does not mention limitations or default behaviors for omitted optional parameters, but those are largely covered by schema defaults. No contradiction with annotations.

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 concise sentences (English and Japanese translation) that front-load the core purpose and output metrics. Every phrase carries information – no filler. It efficiently summarizes a complex tool without redundancy, which is appropriate for the parameter count and nesting.

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 is complex (17 params, nested objects, output schema present) and the description captures the essential function and outputs. Since an output schema exists, return values are documented there, so the description needn't detail them. It does not mention the output_mode parameter, but the schema covers it. Overall, the description is sufficient for an agent to call the tool correctly with the schema's support.

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 description coverage is 100%, so every parameter is already documented with descriptions and defaults. The tool description only restates a handful of inputs (interest rate, LTV, rent, vacancy, etc.) without adding new meaning or clarifying relationships beyond what the schema provides. Per rubric, baseline 3 is appropriate when the schema fully covers parameter semantics.

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's function: a leveraged 10-year real estate pro-forma. It specifies the resource (real estate cash flow) and the specific verb (simulate/試算), and lists distinct outputs (NOI, debt service, DSCR, IRR, equity multiple, sensitivity) that set it apart from sibling tools like simulate_aichi_future or simulate_landscape_impact. The name and title reinforce the distinct leveraged cash-flow focus.

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 provides clear context (when to use: for leveraged cash flow analysis with debt and tax assumptions) but does not explicitly mention alternatives or exclusions. Sibling names indicate other simulation tools exist, but the description does not say 'use this instead of X when...' – leaving the agent to infer from the name and purpose. This is adequate but lacks explicit routing guidance.

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