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

Annotations already indicate read-only, idempotent, open-world, and non-destructive behavior. The description adds valuable operational details beyond annotations: Apple limit is clamped to 50, Google supports 1-250, price filter only applies to Google, and store='both' merges results. This is informative but not exhaustive (e.g., no mention of ordering or pagination).

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 four sentences, front-loaded with purpose, and each sentence adds distinct value: what it does, what it returns, store='both' behavior, and platform-specific caveats. No redundant words or restatements.

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?

Given 8 parameters and no output schema, the description gives a clear overall picture, including return fields and key store-specific constraints. It doesn't detail every parameter (e.g., device, fullDetail), but those are fully described in the schema, making the tool effectively invokable.

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 description coverage is 100%, so the baseline is 3. The description enriches parameter semantics by explaining the 'limit' behavior (Apple clamped vs Google range), 'store' merging behavior, and 'price' filter's Google-only scope, going beyond the schema's phrasing.

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 tool's function: 'Search apps on the Apple App Store, Google Play, or both.' It identifies the resource (apps), specific stores, and lists the returned fields (store, title, developer, icon, price, rating, category, url), which distinguishes it from siblings like get_app or get_charts.

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 concrete usage context, such as using store='both' to fan out and merge results, and clarifies per-store limits. It implies when to use this tool (for general app search) but does not explicitly exclude alternatives or compare with sibling tools, so it falls short of a 5.

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