価格トライアングル・アービトラージスキャン

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

Annotations already indicate readOnlyHint=true and destructiveHint=false. The description adds context by explaining the cross-checking mechanism and the optional live data fetch that requires MLIT_API_KEY, which is not covered by 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?

Two sentences cover the core functionality and use cases, but the bilingual repetition (English and Japanese) adds redundancy. The front-loading of English purpose is effective.

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 presence of output schema, annotations, and high schema coverage, the description is sufficiently complete. It explains the three price sources and signal types but could mention the output format (compact/detailed) more explicitly.

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 covers all 5 parameters with descriptions (100% coverage). The description does not detail individual parameters but provides high-level context on how the tool uses them. Per guidelines, baseline 3 is appropriate since schema does the heavy lifting.

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 specifies the tool's function as a 'Price triangulation arbitrage scanner' that cross-checks three specific land price sources (路線価, 公示地価, 取引価格) and lists concrete use cases (discount buys, inheritance-tax edges, overheated markets). It distinguishes itself from sibling tools by focusing on arbitrage signals across price sources.

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 detecting arbitrage opportunities in real estate but does not explicitly state when to use this tool versus alternatives among the 32 siblings. No exclusion criteria or alternative tool references are provided.

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