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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds value by specifying the concrete response content and the one-product bound, which go beyond the annotations.

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?

One compact sentence that front-loads the return value and then gives the call instruction. No filler, no repetition of schema content.

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 read-only single-product lookup, the description covers what it returns and how to identify the product. It lacks explicit error/not-found behavior and does not enforce the sku-or-slug requirement in the schema, but this is a minor gap given the annotations and simple parameter set.

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 descriptions already document both parameters with examples, so the baseline is 3. The description adds the important selection semantics that the agent should supply sku or slug, which the schema does not express as a mutually-exclusive requirement.

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 full details for one product and enumerates the data areas (description, ingredients, instructions, dimensions/weight, GTIN). It distinguishes itself from sibling list_products by explicitly scoping to a single product and requiring sku or slug.

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 gives clear usage context: use when you need complete details for one product, identified by sku or slug. It does not explicitly mention alternatives or exclusions, but the singular scope and identifier instructions make the intended use unambiguous.

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