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

With only an openWorldHint annotation, the description carries most of the behavioral disclosure burden. It goes beyond the annotation by explaining the pricing model (per region × POI type, not per store), the exclusion of count statistics, and the scope of POI categories. It could add more on result-volume or edge-case behavior, but the disclosed traits are substantive and non-contradictory.

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 front-loaded with the core purpose, followed by coverage, exclusions, typical examples, and pricing. Each section serves a distinct need, and the pricing JSON is compact yet important for agent decision-making. Nothing is redundant or filler.

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 that an output schema exists, the description does not need to explain return values. It provides the necessary context: scope, region requirement, POI categories, exclusions, typical user intents, and billing semantics. This is complete for an agent to decide when and how to invoke the tool.

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%, so the baseline is 3. The description adds a small amount of value by giving typical query phrasings and reiterating the single-region requirement, but it largely restates what the schema already documents about input_text, gov_name, version, and poi_type. It does not significantly deepen parameter understanding beyond the schema.

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 identifies the tool as a query for shopping POI detail lists within a city or district, using explicit verbs like '查询' and specifying the resource ('购物 POI 明细列表'). It also distinguishes itself from sibling POI tools by listing covered categories (超市、商场、购物中心、便利店、专卖店) and explicitly excluding count-statistics queries.

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 states when to use the tool: for queries like '某区超市分布' or '便利店列表' based on an explicit administrative region. It also gives an explicit when-not case ('不回答超市/商场数量统计') and points to the alternative ('请用兴趣点数量指标'), which provides clear guidance beyond the schema.

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