list_categories

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

Annotations already declare readOnlyHint and idempotentHint, covering safety and idempotency. The description adds meaningful behavioral context by specifying the exact return content (categories and post counts), which goes beyond the annotations. There is no contradiction with the 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?

The description is a single concise sentence, directly stating the tool's function without any filler, redundancy, or unnecessary detail. It is efficiently front-loaded with the action and resource.

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, zero parameters, and the existence of an output schema, the description is fully sufficient. It clearly states the resource and return value, while annotations cover behavioral safety and completeness (openWorldHint false).

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 the baseline score of 4 applies. The description correctly implies that no input is required, and there are no parameter semantics to explain 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 uses a specific verb '반환한다' (returns) and clearly identifies the resource: blog categories and their post counts. This makes the tool's purpose unambiguous and distinct from sibling tools like list_articles or search_articles, which focus on articles.

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 provides clear context that this tool returns categories with post counts, making it obvious when to use it (e.g., when needing an overview of blog taxonomy). However, it does not explicitly mention alternatives or situations where another tool would be more appropriate, which would be needed for a 5.

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