yan_diagnose

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is structured. The description adds the non-obvious behavioral fact that it works without WeChat open, but says nothing about what it reports or any failure modes beyond that.

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?

A single front-loaded sentence naming the three things checked, followed by the key runtime condition. No filler or redundancy.

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 parameterless diagnostic tool with annotations covering safety, the description covers what is checked and the notable 'no WeChat needed' condition. It stops short of describing the shape of the diagnostic result, which would help an agent interpret the output.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The description does not introduce spurious parameter-like options.

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?

States a specific verb (检查/diagnose) plus concrete resources: configuration, local service connection, and optional parsers. It is clearly a self-diagnostic tool, distinguishable by nature from the WeChat-reading siblings, though it does not explicitly name any sibling it contrasts with.

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 clause '即使没有打开微信也可运行' implies a troubleshooting/health-check use case that does not depend on WeChat being active, which is useful context. However, it does not state when to prefer this over alternatives or what conditions warrant running it.

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