list_available_stats

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only mentions the output (codes and names) but does not disclose whether the operation is read-only, has any side effects, requires authentication, or has rate limits. Even though a list operation is low-risk, the description lacks explicit behavioral transparency.

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 brief and well-structured: a single sentence stating the purpose, a second sentence clarifying its relationship to search_statistics, and a clear 'Returns' line. Every sentence earns its place, and the critical usage context is front-loaded.

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 there are no parameters and an output schema exists (as indicated by the context signal), the description is complete. It clearly states what the tool does, what it returns, and how it relates to a sibling tool. Nothing essential is missing for an agent to correctly invoke it.

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 tool has zero parameters, so schema coverage is 100% by default. The baseline for 0 parameters is 4. The description does not need to explain parameters, and it correctly references the related stats_field parameter of another tool without confusing it with its own. The description adds no extra parameter semantics, but none are needed.

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 displays a list of available statistical categories (統計分野の一覧), with a specific verb '表示する' and resource. It explicitly connects to search_statistics' stats_field parameter, distinguishing it from sibling tools like get_regional_data or compare_regions. This makes the purpose unambiguous.

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 explicitly states this provides codes usable in the stats_field parameter of search_statistics, which is a clear usage context. It implies when to use it (before calling search_statistics) but does not explicitly state when not to use it or mention alternatives. The guidance is sufficient but could be more direct.

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