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

Annotations already declare read-only, idempotent, open-world, and non-destructive behavior. The description adds useful context beyond annotations: it describes the aggregate output (per-city total and operating counts, sorted descending) and the filtering effect of benefitType, including consistency with list scope ('与列表口径一致').

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?

Two sentences, front-loaded with the aggregate definition and sort order, followed by the optional filter behavior. Every phrase earns its place with no 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?

No output schema exists, so the description must describe returns; it does so by specifying per-city total and operating counts sorted descending. With only one optional parameter and rich annotations, this gives enough context for correct invocation.

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 100% and benefitType is already documented in the schema as '只统计含某类补贴的园区'. The description largely restates this, adding only the note that results stay consistent with list scope. Under the high-coverage baseline, a 3 is appropriate.

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 a specific aggregate resource: per-city totals of parks and operating parks, sorted descending by total. It also identifies the intended use case ('宏观选址用'), which distinguishes it from sibling tools like list_parks (individual park listing) and get_park.

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?

It clearly says when to use the tool ('宏观选址用' / for macro site selection) and explains the conditional benefitType filtering. It does not name alternative tools or state when not to use it, so it falls short of a full when/when-not/alternatives guidance.

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