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

Annotations provide only openWorldHint with no readonly or destructive hints, so the description carries the burden. It states '查询' (query) and '返回' (return), implying a safe read operation. It also clarifies the output type (list of companies) without mentioning side effects or costs beyond the pricing info. This is adequate for a simple query tool.

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 concise, front-loaded with the main purpose, and includes a clear list of inclusions/exclusions and example queries. The inclusion of pricing info is extra but not disruptive. It is well-structured and avoids 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?

Given the tool's simplicity (2 params, 1 required) and full schema coverage, plus the presence of an output schema (per context signals), the description is complete. It covers what it does, what it excludes, gives usage examples, and implies default behavior for year. No critical gaps remain.

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% with descriptions for both parameters. The description adds meaning by implying that if year is omitted, it uses the current year ('当年'). It also provides concrete examples for park_name, but does not elaborate on year format beyond the schema's example. This goes slightly beyond the schema, which earns a 4.

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 purpose: querying the list of newly added companies for a given park and year. It differentiates from sibling tools by specifying it's for parks (not chains) and returns a list, not just counts. The typical question examples reinforce this purpose.

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 specifies what it does not include (other company categories, count-only results), implying that the sibling _num tool should be used for counts. It does not explicitly name alternative tools, but the context is clear. Typical question phrasing helps users understand when to use this tool.

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