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

The description discloses the pricing (¥0.05 per call) and the output behavior (ranked troubleshooting plans), which is useful. However, with no annotations provided, the description carries the full burden of behavioral disclosure. It doesn't mention whether the tool is read-only, whether it calls external APIs, or what the exact output format looks like. The output schema exists but the description doesn't elaborate on it.

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 with the core purpose, followed by parameter guidance and pricing. The examples are useful but the parameter explanations could be slightly more structured. Overall, every sentence earns its place.

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?

Given the tool's simplicity (2 required string params, output schema present), the description covers the essential usage. It includes pricing, parameter semantics, and output behavior. It could be more complete by describing the output schema structure or any limitations, but for a simple diagnostic tool it 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 description coverage is 0%, so the description must compensate. It does: it explains brand as device brand with examples (g120 / s7-1200 / fx5u / hmi / modbus) and symptom as fault symptom with examples (F07452 / 通讯不通 / 启动不转 / 报警灯闪). This adds significant meaning beyond the bare schema, though it doesn't specify exact allowed values or formats.

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 clearly states the tool's function: diagnosing industrial control faults by taking a device brand and fault symptom, and returning troubleshooting plans sorted by match. It also includes concrete examples for both parameters, which makes the purpose unmistakable.

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 provides clear usage context: input brand and symptom, get ranked troubleshooting plans. It also gives example values for both parameters, which helps the agent know what to pass. It doesn't explicitly state when not to use it or name alternatives, but the sibling list shows distinct tools, so the usage context is reasonably clear.

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