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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds genuinely useful behavior context beyond that: the catalog is limited to non-prescription/OTC items and results carry sponsored/featured/new-product flags and facet metadata.

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?

Purpose and scope are front-loaded, and the sibling comparison comes early. The first sentence is dense and long, packing return fields and facet details into one run-on, but nearly every clause carries information an agent can use.

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 an output schema present, return values need not be described, yet the description still summarizes payload shape, and it covers scope, sibling routing, and all parameters. Only minor gaps remain, such as pagination limits or result-count behavior when no matches are found.

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% and the description's parameter text (q required, page 1-indexed default 1, sort codes with default relevance) essentially restates the schema rather than adding syntax or edge-case meaning. Baseline 3 is appropriate when the schema already documents all three parameters.

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 a precisely scoped resource (CVS.com's non-prescription retail/OTC catalog by keyword), and explicitly distinguishes itself from the sibling cvs_category as the same backend reached by keyword rather than category/brand path.

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?

Clearly frames the usage context by contrasting with cvs_category (keyword vs. category/brand path), which lets an agent route between the two. It stops short of stating when-not-to-use or noting that a category/brand lookup may be better for exact-path navigation.

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