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

没有 annotations，因此描述承担行为披露责任。它额外披露了每次调用费用 ¥0.05、输入为话题、输出为标题组，这些是有价值的调用行为信息。不过未说明返回标题数量、错误情况或限制，但结合简单生成类工具和 output schema 的存在，已算充分。

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?

一句话内依次给出核心定位、输入示例、返回结果和价格，信息密度高且无冗余，适合 agent 快速解析。

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?

对仅有一个必填参数、无复杂嵌套、且有 output schema 的工具，描述已覆盖调用所需的核心信息：输入语义、返回内容、费用。没有明显影响正确调用的缺口。

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?

Schema 对参数 q 的描述覆盖率为 0%，但描述中用“输入话题（如 房贷利率下调）”补充了 q 的语义，并给出具体示例。单参数场景下这足以让 agent 理解如何填写。

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?

描述使用明确动词+资源：“输入话题……返回高点击标题组”，并给出具体示例（房贷利率下调），清楚说明这是一个头条标题生成工具。与 viral_hook、xhs_viral_note 等兄弟工具在平台和用途上可区分。

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?

描述隐含了使用场景：当用户需要一个话题的头条爆款标题时使用，但没有显式说明何时不该用、或与其他标题类兄弟工具的取舍。缺少 when/when-not 的明确指导。

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