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

The description adds behavioral context beyond the openWorldHint annotation by clarifying that the tool does not return count statistics and that queries must target a single region. It also includes pricing details (credits per region × POI type, not per store), which is useful for understanding cost behavior. However, it doesn't detail response format or pagination, but the output schema exists to cover 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?

The description is concise and front-loaded with the core purpose, followed by scope, exclusions, and examples. The pricing note is additional but relevant. It's slightly dense with the pricing JSON, but overall efficient and well-structured.

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 moderate complexity (4 params, 1 required, output schema present), the description covers the key aspects: purpose, scope, exclusions, and usage examples. The pricing info adds operational context. It doesn't detail response structure, but the output schema handles that. The description is complete enough for an agent to select and invoke correctly.

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 schema already provides 100% coverage for all 4 parameters with clear descriptions. The description adds value by explaining the overall query intent and the constraint of single-region queries, and clarifies that poi_type is limited to the topic's candidate set. This complements the schema without redundancy, though the schema does most of the heavy lifting.

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 queries POI detail lists for life services and leisure entertainment within a specified city or district, listing covered categories (beauty salons, repair, logistics, gyms, cinemas, entertainment venues). It explicitly distinguishes from count statistics by directing users to a different metric tool, and provides typical query examples, making its purpose specific and distinct from siblings.

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 explicitly states when to use this tool (querying POI details for life services/leisure in a single region) and when not to (for count statistics, use the POI count metric tool). It also specifies the requirement for a single region (city or district) and provides typical query phrasings, offering clear usage guidance and alternatives.

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