read_chapter

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

注解仅有 readOnlyHint=true，描述额外揭示了按需加载和 tailLength 截断尾部内容的行为，并给出了使用目的。未描述返回值结构或缺省行为，但 readOnlyHint 已覆盖安全维度，且未与注解矛盾。

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，第一句点明核心功能，第二句解释 tailLength 的目的，无冗余信息，结构紧凑且信息密度高。

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?

工具复杂度低，Schema 与 readOnlyHint 已覆盖参数及安全语义，描述提供了核心使用上下文。未明示返回格式，但 schema 已说明缺省行为，整体对选择与调用足够完整。

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?

Schema 已覆盖全部 3 个参数（100%），基线为 3。描述对 tailLength 补充了“用于续写衔接”这一使用语义，超出 schema 的节省 Token 说明，增加了额外价值。

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?

描述明确说明工具读取指定故事的章节内容，使用具体动词“读取”和资源“章节内容”，并支持按章节索引按需加载。与 write_chapter、scan_stories 等写/列工具能清楚区分。

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 tailLength 的明确使用场景（续写衔接、节省 Token），说明按需加载的上下文，但未显式提及与 scan_stories 等替代工具的取舍或排除条件。

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