system_info

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

No annotations are provided, so the description carries the full burden. It indicates a read-only retrieval operation and lists categories of information returned, but it does not disclose output format, potential limitations, or side effects. This is minimal but not misleading, warranting a mid-range score.

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 a single concise sentence, front-loaded with the verb, and uses examples to clarify scope. It is appropriately sized with no wasted words.

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 (no params, no output schema), the description provides a basic understanding by listing example fields, but it does not fully specify the return structure or cover all potential fields. Since there is no output schema, the description falls short of being fully complete.

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 has zero parameters and an empty input schema. According to the rubric, 0 params sets a baseline of 4. The description adds no parameter details because there are none to describe.

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 fetches runtime environment system information, listing specific examples (device model, OS version, WeChat version). The verb '获取' (get) and resource are specific, and the tool is distinct from sibling tools focused on page/element operations or wx methods.

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 implies usage when system info is needed, but it does not explicitly provide when-to-use conditions or mention alternatives. No obvious sibling tool overlaps with this purpose, so the context is somewhat clear, but not explicit enough for a higher score.

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