Initializes a conversation-branch workspace: creates the .branches directory and the main line under the given root. Optionally writes initial content to PROMPT.md.
初始化工作区（在 root 下建立 .branches/ 与主线）
| Name | Required | Description | Default |
|---|---|---|---|
| root | Yes | Conversation Branch 工作区根目录 | |
| prompt | No | 主线 PROMPT.md 的初始内容；省略则生成占位模板 |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
注解已声明 readOnlyHint=false、destructiveHint=false、idempotentHint=false，描述补充了具体行为（创建 .branches/ 和主线），但没有说明是否覆盖已有文件、是否要求 root 为空、失败时是否部分创建等。描述与注解不矛盾，但行为细节有限。
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?
描述为单句，简洁且信息密度高，直接说明核心行为。但缺少使用场景或注意事项，略有提升空间。
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?
对于初始化工具，描述覆盖了核心行为，但缺少关键上下文：是否要求 root 为空、是否可重复执行、初始化后如何验证（无输出 schema）。考虑到工具复杂度较低，3 分合理。
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 100%，两个参数（root、prompt）在 schema 中已有描述。描述中提到的 '主线' 与 prompt 参数相关，但没有额外说明 prompt 的格式或默认模板内容。schema 已承担主要说明责任，描述未显著增值。
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?
描述明确说明工具的作用：初始化工作区，在 root 下建立 .branches/ 与主线。动词（初始化）+ 资源（工作区）+ 具体行为（建立 .branches/ 与主线）都清晰，且与兄弟工具（cb_branch、cb_checkout 等）明显区分。
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?
描述隐含了使用场景（首次初始化工作区），但没有明确说明何时使用 vs 不使用，也没有提及替代工具或前置条件（如 root 是否必须为空、是否可重复运行）。虽然从名称和描述可以推断，但缺少显式指引。
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.