list_item_groups

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

Annotations already declare readOnlyHint and openWorldHint, lowering the bar. The description adds the permission requirement (INVENTORY_R), which is a behavioral constraint not present in annotations. It does not contradict any annotations, and the short scope is acceptable given the annotations and output schema.

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 a single, front-loaded sentence that conveys purpose and a usage requirement with an illustrative example. Every word is valuable and nothing is redundant.

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?

With an output schema and strong annotations, the description provides all necessary context: what the tool returns, an example, and a permission requirement. No additional behavioral or return-value details are needed for this simple, parameterless tool.

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?

The tool has zero parameters, so the schema is already 100% covered and no parameter documentation is needed. The description's explanation of what item groups are adds context about the return data, which is sufficient.

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 'Returns item groups' and provides a concrete example ('sets of item variants, e.g. size/color'), making the purpose unambiguous. It distinguishes itself from sibling tools like list_items and list_attributes by specifying the resource type.

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 when to use the tool through the example 'size/color' variants, and the explicit permission requirement 'Requires INVENTORY_R' gives a clear prerequisite. It does not explicitly name alternatives, but the context is sufficient for an agent to differentiate from similar list tools.

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