manage-product-variants

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

No annotations are provided, so the description carries the full behavioral burden and does not meet it. It never says whether updates are partial or full replacement (does omitting price on an update clear it?), whether the operation is atomic across the batch, whether it can fail on duplicate SKUs, or what permissions are needed.

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?

Two tight sentences, front-loaded with the action and followed by the key dispatch rule. No filler, though it is thin rather than efficient—there is room for one more sentence of behavioral detail.

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?

A mutation tool with no annotations, no output schema, and batch array input needs more than an id rule. Missing: partial-update semantics, failure/rollback behavior, interaction with the required 'variants' array, and what is returned after creation.

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%, including detailed notes on strategy, mediaId, inventoryPolicy and optionValues, so the baseline is 3. The description's only added meaning is the id-omitted-vs-present rule, which the schema already states for the id field.

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 pair and resource ('Create or update product variants') and immediately clarifies the upsert discriminator. An agent can distinguish it from delete-product-variants and get-product-variants-detailed, though the description never explicitly contrasts with those 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 id/no-id rule gives clear guidance on how to create vs update a single variant, but there is no guidance on when to use this instead of manage-product-options, add-product-media, or delete-product-variants, and no prerequisites (e.g., product must exist, options must exist first).

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