list_in_app_purchases

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

No annotations are provided, so the description must disclose behavioral traits. It only repeats the tool's name and gives no insight into pagination, return format, default behavior, or any side effects. The schema mentions the limit default, but the description itself adds no behavioral context.

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 at one sentence, which is appropriate for a simple tool, but it is under-specified. It essentially restates the tool name and doesn't front-load any additional useful details, so it feels like a placeholder rather than a well-crafted 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 no output schema and no annotations, the description is the only source for understanding the response. It doesn't mention what fields are returned, how pagination works, or any caveats, so the agent is left without necessary context for a complete tool invocation.

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 provides 100% coverage for both parameters (appId and limit) with clear descriptions, so the baseline is 3. The tool description does not add meaning beyond what the schema already states, but it doesn't need to given the schema's completeness.

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 action (list) and the resource (in-app purchases) with the scope ('for an app'). It is distinct from sibling tools like list_subscriptions or list_builds because the resource is explicitly named. However, it doesn't explicitly differentiate from other list tools, so it misses the top score.

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 provides no guidance on when to use this tool versus alternatives or any prerequisites beyond the implicit appId. There is no mention of context, exclusions, or related tools, so the agent receives no usage direction beyond the obvious.

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