yn_status

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

由于没有 annotations，描述承担了行为透明度的全部责任。它说明了工具是只读的状态检查，并披露了返回内容涉及鉴权、连接和上游工具数量，让 agent 能预期调用结果。但未说明该检查是否发起网络请求，略有保留，不过对诊断型工具已足够。

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?

一句话同时包含工具功能、返回内容和使用场景，信息密度高且没有冗余。前段描述状态检查，后段给出诊断触发条件，结构紧凑高效。

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?

对于零参数、无输出 schema 的状态检查工具，描述已列出关键输出维度（API Key 配置、端点、连接状态、工具数量），足以让 agent 正确理解和调用。没有缺失的关键信息。

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?

工具无参数，且 schema 覆盖率为 100%，因此参数语义不是负担。描述没有引入参数相关细节，这符合零参数工具的基线评分。

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?

描述明确说明了工具的功能（检查配置与连接状态）以及返回的核心信息（API Key 是否配置、端点、连接就绪状态、工具数量），与兄弟工具 yn_list_tools、yn_refresh_tools 的用途有明显区分。动词和资源清晰，不存在歧义。

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?

描述明确给出了使用时机：当笔记类工具报错时，先调用此工具判断是鉴权问题还是连接问题。虽然没有显式列出何时不使用或对比兄弟工具，但已提供清晰的诊断场景，足以引导 agent 在合适时调用。

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