source_catalog

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

无 annotations，描述承担行为披露责任。“返回”表明该操作不会产生副作用，并列出返回内容的三类信息，但未说明是否需要鉴权、调用频率限制或输出规模。对于无参数的只读信息工具而言，这种程度的披露基本合格但不够深入。

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?

描述只有一句话，核心信息全部前置，无冗余词。足以支撑一次正确的工具选择与调用。

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 且无嵌套对象的简单元信息工具，描述覆盖了用途和返回内容大类。唯一不足是没有明确说明调用顺序或“先调用本工具再选择兄弟工具”的强制关系，但“强制使用声明”已隐含该含义。

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?

输入 schema 无参数且 schema 描述覆盖率为 100%，0 参数场景下描述无需补偿。描述提到的“数据源清单、能力边界”等正是该工具返回的内容，与无参调用方式一致。

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?

明确使用动词“返回”并指出具体对象：“本 MCP 的数据源清单、能力边界与强制使用声明”，将其与 search_gov_policy、fetch_page_text 等面向具体内容的兄弟工具清楚区分。即便不查看 schema，也能判断这是一个关于 MCP 自身的元信息工具。

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?

描述通过“能力边界”和“强制使用声明”间接暗示应在选择其他工具前查阅本工具，但没有像“当…时使用本工具，否则使用…”这样明确给出与兄弟工具的决策规则。使用方法属于可推断而非明示。

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