chewy_variants

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

With no annotations, the description carries the full behavioral burden and meets it thoroughly. It discloses the family-return behavior (any variant id returns the whole family), the is_requested flag, the fields included (part number, price, Autoship price, stock, images, defining option), and the limitation that only the defining option is returned.

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 dense but every sentence earns its place—purpose, return contents, parameter semantics, sibling differentiation, and scope limitation. It is front-loaded with the core action and the comparative framing against chewy_product is efficient. No filler or redundancy.

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 single-parameter tool with no output schema and no annotations, the description is remarkably complete. It explains the input, what is returned, the family/flagging behavior, and the boundary of what is not returned (full attributes) with a pointer to the correct sibling. Nothing necessary for correct invocation is missing.

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?

Even though schema coverage is 100%, the description adds substantial meaning to the id parameter: it clarifies that any variant's id from a PDP URL works, that it returns the entire variant family, and that the requested variant is flagged. This goes well beyond the schema's bare statement that id is a numeric PDP URL id.

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?

Opens with a specific verb and resource: 'List every size/flavor variant of a Chewy product.' It clearly distinguishes itself from chewy_product by explaining what that sibling cannot do, and from chewy_item_attributes by noting it returns only the defining option. An agent can immediately tell this tool apart from its 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 explicitly states when to use this tool: when the user needs the full variant family and sibling prices, a question chewy_product cannot answer. It also gives an explicit exclusion—'Only the defining option is returned... use chewy_item_attributes for that'—routing the agent to the correct alternative.

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