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

With no annotations present, the description carries the burden of behavioral disclosure. It communicates that the operation is a read ('조회') and that admin rights are required, which is useful. It does not describe output format, report scope, potential failure behavior, or whether the statistics are aggregated or filtered in any way.

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 extremely concise: two short sentences with no filler or redundant information. It front-loads the core purpose and immediately states the key access requirement, which is appropriate for a tool with no parameters.

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?

For a zero-parameter read-only tool, the description provides a usable baseline: the agent knows what to call and under what permission condition. However, there is no output schema and the description does not explain what the returned ad performance statistics will include, which leaves some ambiguity about expected results.

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 input schema has zero parameters and 100% schema description coverage, so there are no parameter semantics for the description to clarify. The baseline for a no-parameter tool is 4, and the description correctly does not invent parameter details.

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 action ('조회합니다' / retrieves) and the resource ('광고 성과 통계' / ad performance statistics), so an agent can understand what the tool does. It does not explicitly differentiate it from sibling stats tools like get_site_stats or get_price_stats, but the ad-specific resource is reasonably distinctive.

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 mentions an admin permission prerequisite, which is a form of usage constraint. However, it provides no guidance on when to use this tool over the related statistics tools or which conditions should trigger this tool versus get_site_stats/get_price_stats.

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