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

No annotations exist, so the description carries the full burden. It usefully discloses that results are rank-ordered, capped at 50, and include full details, and that the store value is 'google' or 'apple'. It says nothing about rate limits, auth, pagination, or whether this is strictly a read-only operation.

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 sentences, zero filler. The capability statement comes first and the usage guidance follows, so an agent can stop reading after sentence one if it only needs the what.

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-value detail need not be spelled out, and the description still summarizes the shape (ranked apps with full details). The main omission is any mention of the country parameter, which an agent must discover from the schema alone.

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 0%, so the description must compensate. It clarifies the store parameter's accepted values ('google or apple') and implies a 50-result ceiling on limit, but never mentions the country parameter or the limit default of 20, leaving one of four parameters fully undocumented.

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 (search) and resource (App Store / Google Play apps), plus what is returned: ranked apps with full details. It functionally separates itself from siblings app_store_details and app_store_reviews, though it never names them explicitly.

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?

"Use for ASO keyword research or finding competing apps" gives positive use cases, but there are no exclusions or explicit routing to the sibling detail/review tools. Usage is implied rather than prescribed.

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