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

无注解时描述需承担全部行为披露。它说明了需要有效 Key、匿名不可用（认证要求），以及返回结果包含 source 字段标识发起者，并具体描述了 action_call 和 push 的 payload 结构，揭示了部分返回内容的细节。但仍未说明速率限制、分页行为或完整返回格式。

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?

描述紧凑，用短句列举了关键信息：功能、类型枚举、参数、返回特征、认证要求。没有冗余填充，信息密度高。但将多个不同性质的信息（参数、返回结构、认证）堆叠在一个段落中，结构感稍弱。

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?

工具无输出 schema，描述需要传递足够的返回信息帮助代理理解结果。它提到了 source 标识和某些 payload 字段，但缺乏对整体返回形状（如事件列表的通用字段）的说明。参数整理在 schema 描述为零的情况下也不够充分，整体完整性有提升空间。

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 覆盖率为 0%，5 个参数中只有 slug 在描述中明确标注为必填，type、from/to、limit 的参数含义和格式完全未在描述中说明。描述的补充信息非常有限，仅提到 limit ≤ 500，但未补充 from/to 的格式预期或 slug 的指代。基线 3 因低覆盖率应提高要求，此处描述未充分补偿。

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?

描述清晰表达了具体动作和对象：跨会话按类型拉取事件，倒序排列。列出了所有可用的 type 枚举值（chat_user/chat_assistant/track/action_call/page_open/push），有助于限定用途。但未明确区分它与兄弟工具 get_session_log、list_sessions 等的关系，代理需要自行推断。

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：按事件类型查询，且有计费和排障的提示，但没有明确说明何时应该使用此工具而不是 get_session_log 或 list_sessions。没有列出排除条件或替代方案。

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