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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower; the description still adds real value by noting 'Public; no OAuth required' (auth requirement) and that results are paginated public links and IDs. It doesn't discuss rate limits or cursor expiry, which the schema covers anyway.

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 tight sentences with the core action front-loaded, followed immediately by the disambiguation and the public/read-only facts. No filler or repetition of schema content.

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, return-value explanation is unnecessary, and the description covers the pieces an agent needs: what it searches, why it differs from search_products, auth posture, and pagination. Nothing material is missing.

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 q, page, cursor, and per_page including their mutual-exclusion rules and defaults. The description only alludes to pagination generally and adds no format or syntax detail beyond the schema, making the baseline 3 appropriate.

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 (find/browse) and resource (brands) plus its distinctive capability (typo suggestions), and explicitly distinguishes itself from the sibling search_products: 'this finds brands, not products.' An agent can route correctly without opening either 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 clear usage context and an exclusion ('this finds brands, not products'), plus a downstream chaining hint that returned IDs feed search_products.brand_id. It stops short of a full when-to-use/when-not statement against every alternative, but the differentiation is explicit.

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