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

注解已声明 destructiveHint=true，描述额外补充了“需要登录”的权限前提和“已取消/已结束不可再取消”的状态约束，为代理提供了注解之外的行为信息。描述与注解一致，不存在矛盾。

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?

两句话都信息密集且无冗余：第一句说明操作和登录要求，第二句说明状态限制。关键信息前置，结构清晰，没有任何浪费。

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?

该工具只有一个必填参数、无输出 schema，复杂度很低。描述配合注解已完整覆盖登录要求、操作效果、状态前置条件和破坏性语义，足以让代理正确调用。

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?

参数 activityId 在 schema 中已有完整描述（“活动 id”），schema 覆盖率为 100%，描述没有为参数增加额外语义。按高覆盖率基线评为 3 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?

描述使用明确动词“取消（下线）”和资源“我发起的某个活动”，准确表达了操作对象与范围。与同族的 cancel_need、unpublish_need、update_activity 等工具在语义上可清楚区分，不会让代理产生混淆。

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?

明确给出登录前提，并说明“已取消/已结束的活动不能再取消”这一使用限制，帮助代理避免无效调用。但没有显式指出何时应改用 update_activity 等替代工具，因此未达到最高分。

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