Get variant

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds genuinely new context: the required OAuth scope (edit_products) and the note that no local effect approval is required, which is behavior an agent cannot derive from 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?

It is a single tight sentence with the endpoint and scope front-loaded and no filler. The leading 'Get variant.' is slightly redundant with the title but costs almost nothing.

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-entity fetch with full schema coverage, rich annotations and no output schema, the description supplies the endpoint, scope and safety context an agent needs. It omits what the response contains and the not-found behavior, which is a minor gap given no output schema exists.

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 all four parameters are already documented in the schema, including the 'exact opaque provider ID' semantics and the account label caveat. The description adds no parameter-level meaning beyond that, so the 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?

The description names the resource (variant) and pins it down with the exact native endpoint path including the product_id / variant_category_id / variant_id hierarchy, so an agent knows precisely what entity is fetched. It is more than a restatement of the name, though it never explicitly contrasts itself with get_variant_category or list_variants.

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?

There is no when-to-use guidance, no statement of when to prefer list_variants over this single-fetch tool, and no mention of prerequisites or failure cases. Usage must be inferred entirely from the endpoint path.

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