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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered; the description usefully adds that this is a reference/enumeration lookup whose output feeds other tools' parameters. It does not say whether the value set is static or could change, which is the one behavioral fact still missing, so it falls short of a 5.

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, purpose front-loaded before the usage triggers, with zero filler. The ten-value enumeration is informative but somewhat long and overlaps with what the output schema already declares, keeping it just short of a 5.

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?

Zero parameters, an output schema that carries the return shape, and annotations that cover the safety profile — the description only needed to say what it fetches and when to call it, and it does both. Nothing an agent needs to invoke this correctly is absent.

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 takes zero parameters, so the baseline is 4 by rule. The description's enumeration of codes adds meaning about what the tool yields rather than about inputs, which is appropriate here and needs no further compensation.

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 names a specific verb (가져옵니다 / fetch) and resource (분야(섹션) 코드와 한글 분야명), and enumerates the exact code values returned, so the agent knows precisely what comes back. It also names the two sibling tools that consume these codes (list_popular_news, list_recommended_articles), distinguishing it from the other list_* news tools.

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?

It states explicit trigger conditions ('어떤 분야가 있어?', '뉴스 카테고리 목록', or checking a section code) and implicitly defines when-not-to-use by pointing to the tools that take these codes as input. An agent can decide between this and the article-listing siblings without inference.

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