compare_prefectures

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

Annotations already indicate readOnlyHint=true and destructiveHint=false, so the description does not contradict them. However, the description adds minimal behavioral context beyond stating 'Markdown output' and the ranking nature. It does not discuss data sources, update frequency, or limitations, which would be useful given no output schema.

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 short sentences in English and Japanese, front-loading the core functionality and output format. Every word is informative, with no redundancy. It is highly concise and well-structured.

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?

Despite having 7 parameters and no output schema, the description only mentions 'Markdown output' and ranking. It omits details on return structure, such as fields included or how the ranking is presented. While it covers the basic purpose, it lacks completeness for an agent to fully understand the output without additional context.

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 provides descriptions for 4 of 7 parameters (57% coverage), and the description lists some metrics but does not explain any parameter in detail. For example, 'metrics' has an enum but the description only mentions a few. Since schema coverage is moderate, the description adds marginal value; baseline 3 is appropriate.

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 compares up to 5 prefectures on specific metrics (land price, population, risk, investment score) and outputs markdown rankings. This distinct purpose differentiates it from sibling tools like analyze_commute_accessibility or forecast_land_price_trend, which focus on different analyses.

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 guidance is provided on when to use this tool versus alternatives. The description merely states what it does, without clarifying when it is appropriate or when another sibling tool (e.g., cross_analyze_real_estate_market or generate_area_report) might be better suited for broader or deeper analysis.

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