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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds limited extra behavior: 'when available' signals that some counts may be absent, and it clarifies the return is metadata not catalog items. It does not describe auth, rate limits, or fallback behavior when counts are missing.

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 sentences, no filler. The scope statement is front-loaded and the sibling-routing caveat follows immediately, so the agent gets the essential distinction first.

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 present, the description need not enumerate return fields, and it covers purpose, the metadata-vs-catalog split, and the conditional availability of counts. It leaves the overlap with other store-adjacent siblings (e.g. allbirds_sitemaps, allbirds_page) unaddressed, a minor gap.

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 takes zero parameters, so there is nothing for the description to document and the baseline is 4. The description correctly does not invent parameters, though it also offers no invocation-time semantics to add.

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 (Report) plus concrete resources (storefront domain, currency, country, published product/collection counts), and explicitly contrasts itself with allbirds_products and allbirds_collections. An agent can identify what this returns and what it does not without opening the schema.

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?

Gives both a positive condition (fetch store metadata) and an explicit alternative with the condition that selects it ('use allbirds_products or allbirds_collections to browse the catalog'). The when-to-use boundary is stated rather than implied.

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