人口・世帯数（月次・町丁別）

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

No annotations provided, so description bears full burden. It indicates the tool is read-only (returns data) and mentions client-side graph creation, but lacks details on authentication, rate limits, or side effects. Given the tool's nature, the disclosure is adequate but not comprehensive.

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?

Description is concise (3 sentences), front-loaded with purpose, and includes all key usage details without redundancy. Every sentence contributes meaningful information.

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?

With no output schema, the description explains what data is returned (population, household counts) but not the format. Given the 100% schema coverage and clear parameter descriptions, it is mostly complete; lacking output structure is a minor gap.

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, but the description adds value by explaining level values ('area=町丁別 / district=地区別 / city=市全体') and implicitly clarifying how area and district serve as filters.

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?

Description explicitly states it returns population and household counts by town for Oyama City, with filtering options. Clearly distinguishes from sibling tools like get_age_distribution and list_areas, which serve different purposes.

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?

Describes filtering parameters (period, district, area, level) and aggregation granularity, providing context for when to use different levels. However, it does not explicitly state when to prefer this tool over alternatives like get_age_distribution.

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