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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly mentions the cost per use (¥0.05), the operation's purpose, and that it returns a mapping, which implies a non-mutating behavior. It could mention potential error cases or limits, but the core behavior is transparent.

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 brief and front-loaded: the main purpose appears first, followed by input format, output type, cost, and a useful example. Every sentence serves a distinct purpose with no filler.

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?

The tool is simple (one parameter) and has an output schema, so the description does not need to explain return values. It covers the input format, the purpose, and the cost, which is the most critical operational detail. Nothing an agent needs to invoke it correctly is missing.

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?

The input schema provides only a string parameter with 0% description coverage. The description fully compensates by explaining that the input must be a comma-separated variable list and gives a concrete example ('Motor1_Run,Valve3_Open,...'). This adds essential meaning beyond the bare schema.

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 states the tool generates Chinese annotations for PLC variable tables, with a clear verb ('生成') and resource ('PLC 变量表'). It includes a concrete example of input format and distinguishes itself from the unrelated sibling tools.

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 clearly indicates when to use the tool (when Chinese comments for PLC variables are needed) and provides the exact input format with an example. It does not explicitly state when not to use it, but the sibling tools are clearly unrelated, so the context is sufficiently clear.

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