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

With no annotations provided, the description carries the full burden and does well: it states the side effect (writing settings and chapters to disk), the destination path, and the mode-dependent behavior where cloud mode returns guidance instead of writing. It could still mention overwrite behavior or prerequisites, but the core behavioral contract is clearly disclosed.

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?

The description is compact and front-loaded: it states what the tool is for before giving the mode-specific outcome. Both sentences earn their place, though the parenthetical is slightly dense and could be cleaner for an agent parsing it quickly.

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?

For a tool with no output schema and no annotations, the description covers the essential invocation context: when it writes, where it writes, and what cloud mode returns. It doesn't describe the exact return shape or error/failure behavior, but for this simple two-parameter tool the coverage is largely sufficient.

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 coverage is 100%, so the schema already documents work_id and local. The description adds the local-vs-cloud behavioral distinction, which gives some extra meaning to the local parameter, but it doesn't materially enrich the parameter semantics beyond what the schema already provides.

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?

The description names a specific action ('落盘同步'), the resource ('作品设定与全部章节'), and the exact destination path. It also distinguishes the local write behavior from the cloud guidance behavior, making the tool's purpose unambiguous even among siblings like export_work or export_kd.

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?

The description gives useful context: this is a manual, local Python zui-lang tool, and cloud mode returns guidance instead of writing. However, it does not explicitly say when to prefer this over sibling tools such as export_work or export_kd, nor does it state conditions where this tool should not be used.

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