Preflight: check setup before starting

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

在无任何注释的情况下，描述明确声明'只读、无副作用'，直接披露了关键行为特性。同时说明返回的note用于引导用户，提供了结果处理方式。这完全承担了行为披露的责任，没有矛盾。

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?

描述虽然较长但信息密度高，每条检查项都是必要的。结构上先给出使用前提，再列举检查点，最后给出条件处理，逻辑清晰，没有冗余内容。

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?

对于零参数且无输出schema的工具，描述覆盖了使用场景、检查内容、结果处理方式（note引导）以及后续动作（agent_start），足够让代理正确调用。虽未详细描述返回格式，但已提及note的存在，在无输出schema下可接受。

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?

工具无参数，且schema覆盖100%为空，符合基线4。描述无需添加参数含义，因为不存在参数，因此保持基线评分。

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?

描述明确指明了工具的功能：在启动前进行环境自检，列出所有检查项（MCP注册、浏览器启动、marionette连接、worker配置），并说明用途是确保环境就绪后再启动agent。这与兄弟工具如agent_start形成明确区分，因为它是前置检查步骤。标题和描述都强化了这一目的。

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?

描述明确说明使用时机：'开跑前先调这个自检'，并给出条件性指引：未就绪时按返回的note引导用户，就绪后调用agent_start。虽然没有明确列出替代工具或何时不使用，但通过关联agent_start提供了清晰的上下文。

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