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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuinely new behavior: results come back as two labeled groups (attractions and business_districts) each carrying distance, and the call triggers a 'PowPow 附近发现' card UI. It doesn't discuss empty results or error behavior, keeping it short of a 5.

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 tight sentences: first the purpose and complement, then the mandatory confirmation rule, bolded and front-loaded where it matters most. The location-confirmation clause duplicates schema text rather than adding a new fact, which is the only waste.

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?

An output schema exists, so return values need not be enumerated, and the annotations cover read-only/open-world semantics. The description still supplies the two-group output shape, the UI surface, and the critical pre-call interaction rule—everything an agent needs to invoke it 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?

Schema coverage is 100%, and the schema's `place` description already contains the 'ask which place first' guidance, so the description largely restates it. `radius_meters` and its 3000 default are never mentioned in the description. Baseline 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?

States a specific verb and resource (查找某地点附近的景点与商圈) and explicitly positions it against a sibling capability (与「附近的数字人」互补). An agent can distinguish it from find_nearby without opening either schema.

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?

Gives both a positive trigger (nearby discovery) and an explicit precondition: when the user says「我附近」, ask which city/business district rather than guessing coordinates. The alternative (附近的数字人) is named, so routing is unambiguous.

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