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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds real context beyond that: results are scoped to published/public campaigns only, each campaign carries its nested acts list, and the output is rendered as a 'PowPow 附近发现' card component — the last point materially affects how an agent should present results.

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?

Three short sentences, front-loaded with what is listed and immediately followed by the embedded-acts detail and the display behavior. No filler, though the card-rendering sentence is somewhat UI-centric for a tool description.

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?

With an output schema present and full annotation coverage, the description need not explain return values, and it still usefully flags that acts are nested inside each campaign. A note on whether the list is paginated or exhaustive ('全部') would close the remaining gap.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The description correctly implies no input is needed and instead spends its words on output shape.

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 verb and resource ('列出 PowPow 的全部公开活动') and gives a concrete example ('北京 100 家博物馆' 打卡活动), plus the important detail that each campaign embeds its acts list. It does not name a sibling to contrast with (e.g. find_nearby / nearby_attractions), so differentiation is implicit rather than explicit.

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?

'用于 agent 介绍当前可参与的活动' gives a clear intended use case, which is more than nothing. However, there are no exclusions or alternatives — nothing says when an agent should call nearby_attractions or find_nearby instead of this, even though those siblings are likely adjacent in purpose.

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