List variants

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

Annotations already signal readOnlyHint=true and destructiveHint=false, so the read-only nature is covered. The description adds useful conceptual context about variants being sellable units, but it does not describe behavior such as pagination, default limits, or open-world implications beyond what annotations and schema already convey.

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 short sentences with no filler. The first sentence front-loads the action and key filtering capability, while the second provides a concise definition that helps distinguish variants from items; every word earns its place.

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 list operation with no required parameters and strong schema descriptions, the description is largely complete. It explains what a variant is and that filtering is optional, while the schema covers the individual filters. The absence of output schema and pagination details is a minor gap, but the combination of description, annotations, and schema is sufficient for a competent agent.

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 high at 89%, and most parameters already have meaningful descriptions such as 'Exact SKU match' and 'Include soft-deleted records.' The description adds a conceptual mapping to 'SKU or parent item,' but this largely restates what the schema already communicates, so it meets the baseline without elevating it.

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 operation ('List item variants') and clarifies the resource by defining a variant as 'the sellable unit that inventory and receipts refer to.' It does not explicitly differentiate from sibling tools like get_variant or list_items, but its scope is unambiguous enough for selection.

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 implies usage through 'optionally filtered by SKU or parent item,' indicating this is the list-oriented lookup for variants. However, it gives no explicit when-to-use guidance, exclusions, or comparison with nearby siblings such as get_variant or list_items, so the agent must infer the appropriate context.

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