Fetch CVS.com's full brand directory with names and paths, then use each path as the /cvs/category parameter to browse that brand's products.
CVS brand directory. Returns CVS.com's full brand directory (name and path). Each brand's path is directly usable as GET /cvs/category's path parameter to browse that brand's products.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v1.16.2Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden. It states it 'Returns' data, implying a read-only operation, but offers no additional behavioral details such as data volume, pagination, or caching. It doesn't contradict annotations (none exist) but adds minimal transparency beyond the return content.
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 tight sentences with zero filler. The first sentence front-loads the purpose ('CVS brand directory'), and the second adds a valuable usage note about the path parameter. Every sentence earns its place.
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?
For a simple directory with no parameters, no output schema, and a straightforward return type, the description is fully sufficient. It tells the agent what the tool returns and how to apply that output downstream, covering everything needed to invoke it correctly.
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?
The tool has zero parameters, so the description has no parameter semantics to explain. Per calibration, a 0-parameter tool receives a baseline of 4; the description correctly omits any parameter details.
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 returns CVS.com's full brand directory with name and path, using a specific verb and resource. It distinguishes from category tools like cvs_categories and cvs_category by focusing on brands, though it doesn't explicitly name those siblings.
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 a concrete usage pattern: each brand's path can be fed to GET /cvs/category. However, it doesn't state when to choose this tool over alternatives (e.g., cvs_categories for category lists) or any exclusions, leaving the selection criteria implicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.