list_available_dates

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

没有任何 annotations，因此描述需要承担行为披露职责。它明确说明这是只读的“列出/查看”操作，并交代了返回 JSON 列表和对比结果，没有暗示修改或破坏行为。虽然未提远程访问延迟或权限要求等细节，但对于一个 list 类工具，行为信息已经比较充分。

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?

描述由核心一句话、参数说明、返回说明和示例组成，结构清晰、信息密度高，最重要使用方式被放在靠前位置。不过首句“列出本地/远程可用的日期范围”和后续描述存在轻微语义重合，所以不是满分级别。

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?

工具本身只含一个可选参数，复杂度很低；描述已经覆盖了参数取值、默认行为、返回格式和典型调用方式，并给出了具体示例。上下文提示中存在 output schema，所以不需要展开逐字段返回值，整体对安全正确调用已经足够完整。

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?

input-schema 对 source 只给了字符串类型和默认值，没有描述参数含义，描述则完整补充了 local、remote、both 三个取值及各自语义，还明确默认情况下会同时列出并对比。额外给出了 list_available_dates(source="local") 的调用示例，充分弥补了 schema 参数描述缺失的问题。

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?

描述以“列出/查看”明确动词，资源限定为“本地/远程可用的日期范围”，并说明返回 JSON 格式的日期列表与对比结果。该用途与同组的新闻查询、趋势分析等兄弟工具清楚区分，agent 不会混淆其职责。

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?

描述给出了 source 参数的三种取值及默认行为，也提供了调用示例，能够让 agent 推断出“查看哪些日期有数据”时使用此工具。但没有明确指出何时不应使用，也没有和 resolve_date_range、get_news_by_date 等相近工具做选择性说明。

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