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

Annotations declare readOnly and non-destructive, but the description adds critical behavioral context: latency (5-20 seconds), error handling (not-ready error, no charge, retry after a minute), and pricing ($0.005 per keyword). These are non-obvious operational details that an agent needs to invoke correctly.

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 two sentences, front-loaded with what it returns, followed by operational details. It is efficient and every sentence contributes useful information, though it could be slightly tighter.

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 the absence of an output schema, the description adequately explains the return format (ordered apps with rating and reviews) and important invocation details like latency, error handling, and cost. It could mention pagination or rate limits, but it covers the essentials for a read-only search tool.

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 80%, so most parameters are documented in the schema. The description does not add meaning beyond the schema for parameters like depth, store, country, or language; it only mentions 'keyword' implicitly. Baseline 3 is appropriate.

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 what the tool returns: an ordered list of apps a store's search returns for a keyword, plus rating and review data. It's a specific verb+resource, but it doesn't explicitly distinguish itself from sibling tools like app_keywords or keyword_volume, which could also relate to search.

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?

There is no explicit guidance on when to use this tool versus alternatives such as app_keywords or keyword_volume. The description only mentions an error-and-retry behavior, not when to choose this tool over siblings.

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