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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds that the tool 'Returns a widget card with the product details, image, price, and checkout button,' which informs the agent of the output structure beyond the annotations. No additional side-effect warnings are needed for a read-only lookup.

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 three sentences, each with a distinct purpose: primary action, usage context, and exclusion/return. It is concise without redundancy and front-loads the most critical information.

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 read-only product lookup with two parameters, the description covers purpose, usage boundaries, and return format. No output schema is needed for a widget card, and the tool's behavior is fully described with the context and exclusions.

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 100%, with descriptions for both sku and title, including an example SKU and fuzzy-match note. The description's mention of 'by SKU or title' adds no new information beyond the schema, so a baseline score of 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 opens with 'Get full details for a specific product by SKU or title,' providing a clear verb, resource, and lookup method. It explicitly differentiates from browsing/recommendation tools by directing to search_products or skincare_recommend, removing ambiguity among 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?

It states 'Use when the user asks about a specific product by name (e.g. ...)' and provides explicit exclusions: 'Do not use for browsing or recommendations — use search_products or skincare_recommend.' This gives the agent clear decision criteria.

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