List brands

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

Annotations already cover read-only, idempotent, non-destructive, open-world semantics, so the bar is lower. The description still adds genuine, non-obvious behavioral context: counts include out-of-stock products, and brands exist only for products tagged with the shop's brand attribute. Ordering and return fields are also disclosed. Pagination/limits are left to the 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?

Three sentences, front-loaded with what the tool returns, then the routing use, then the data caveats. No filler; every sentence carries a distinct piece of information.

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 simple read-only list tool with full schema coverage and rich annotations, this is complete: purpose, scale, ordering, return fields, intended consumer, and the caveat about which brands exist are all present. No output schema exists, and the description already covers the shape of the response.

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%, so the schema already documents `limit` and `query` (including a Persian example). The description adds nothing about parameter syntax, so the baseline 3 applies. The example brand names loosely illustrate `query` matching but do not extend the schema's meaning.

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 and resource ("List brands"), plus scale (~150), example values, and the exact return fields (slug, product count) with ordering (biggest first). It also distinguishes itself by naming the consuming sibling bn_browse, so an agent can place it without opening a 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?

Explicitly routes the agent: "Use to get the slug for bn_browse's `brand`." That is a concrete use case tied to a named sibling. It lacks explicit when-not guidance, but the brand-attribute caveat effectively tells the agent when results will be empty.

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