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

Annotations already establish that this is a read-only, idempotent, open-world, non-destructive operation. The description adds useful behavioral context about the two output modes and a brief disclaimer, though it does not discuss auth, rate limits, 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 compact and front-loaded: core retrieval behavior comes first, followed by the two modes and a short disclaimer. There is little wasted wording.

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 three optional parameters, full schema coverage, rich annotations, and an output schema, the description is complete enough for correct invocation. It covers both modes and the nature of the data without needing to restate schema details.

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 schema already defines limit, ticker, and minRatings. The description adds meaning for the ticker parameter by explaining the mode switch, but it does not add semantics for limit or minRatings beyond the schema.

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?

Clearly states that this returns app-store ratings for public companies' apps and distinguishes the ticker mode from the no-ticker mode. The resource and scope are specific enough to separate it from sibling financial-data tools.

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?

Explains when to provide a ticker versus when to omit it, including what each mode returns. It does not name a sibling alternative or explicitly state when not to use it, 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.