list_districts

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

No annotations provided, so the description carries the full burden. It clearly states the tool is a read-only query that returns a list. While it doesn't disclose data source or caching, the behavior is simple and transparent for a list tool.

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 a two-sentence structure: first sentence states the core purpose, second provides usage guidance and alternatives. No unnecessary words or repetition.

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 tool's simplicity (no parameters, returns a fixed list), the description completely covers its purpose and referral to sibling tool search_apartments for more detail. The presence of an output schema further reduces the need for describing return structure.

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 baseline is 4. The description adds value by explaining what the list contains (17 cities/provinces), which goes beyond the empty schema.

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 returns a list of 17 nationwide cities/provinces (전국 시/도 17개 목록). It provides a specific verb and resource, distinguishing it from siblings like search_apartments which handle more specific districts.

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 tells when to use this tool (for top-level districts) and when to use an alternative: for more specific areas like 구/동, the agent should directly use the district parameter of search_apartments. This provides clear contextual guidance.

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