update_inventory_variant

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

Annotations already indicate the tool is idempotent and not read-only. The description adds behavioral context about duplicate rejection. However, it lacks details on authentication needs, rate limits, or what happens to omitted fields, which would be valuable given the lack of explicit annotation on these points.

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 extremely concise with two sentences. The first sentence immediately states the core purpose, and the second adds essential details. No extraneous words or redundancy.

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?

Given 5 parameters and an output schema, the description covers variant identification, product context, and duplicate rejection. However, it omits the 'category' parameter entirely and does not clarify whether updates are partial or full. While the output schema exists, the description could better specify which fields are updatable.

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% but with generic descriptions ('a string that will be trimmed'). The description clarifies that 'variant' accepts multiple identifiers and 'product' is optional context. However, 'category' is not addressed, and 'name' and 'sku' are only implied via 'rename'/'change SKU', adding limited semantic value beyond the schema.

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 renames and/or changes the SKU of an inventory variant. It distinguishes from sibling tools like create_inventory_variant or delete_inventory_variant by focusing on updates. However, it does not mention all updatable parameters (e.g., category) from the schema, slightly reducing clarity.

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 provides guidance on how to specify the variant ('accepts ID, exact name, or exact SKU') and when to include product ('pass when needed'). It also notes the rejection of duplicates, which is critical for correct usage. However, it does not explicitly contrast with alternatives like create_inventory_variant for new variants.

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