List variants

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds genuinely new behavioral context: the required scope 'edit_products' and the note that no local effect approval is required, which an agent cannot derive from the structured fields.

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?

Compact and front-loaded: identification first, then endpoint and scope. Dense but every clause carries weight; only the title-like restatement 'List variants' is redundant with the tool name.

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 scoped read-only list tool with full schema coverage and annotations declaring the safety profile, the description covers identification, endpoint, and authorization scope. Pagination or result-shape guidance is absent, but no output schema exists and this is a low-complexity operation, so the gap is minor.

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%, so the schema already documents all three parameters including required product_id/variant_category_id and the account selector. The description adds no parameter-level detail beyond what the schema provides; baseline 3 applies.

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 and resource ('List variants') and pins it to the native endpoint GET /products/:product_id/variant_categories/:variant_category_id/variants, which unambiguously separates it from get_variant, list_variant_categories, and list_products. It does not explicitly name a sibling to contrast with, so it falls short of the top mark.

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 discloses the required scope ('edit_products'), which is real usage context for authorization. However, it gives no when-to-use/when-not guidance or routing to alternatives such as get_variant for a single variant or list_variant_categories for the parent level.

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