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

Beyond the readOnly/idempotent annotations, the description discloses the return composition, grouping order, the fallback comment for missing pricing/stock, per-link fields, and the no-data-no-charge billing rule. This gives the agent a very accurate model of what will happen.

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 dense but every sentence conveys a distinct fact: scope, grouping order, output fields, caveat, and cost. It is front-loaded with the core purpose and avoids filler.

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 one-parameter read-only tool with no output schema, the description supplies enough detail for an agent to invoke it correctly and interpret the returned data. It also covers edge cases such as missing fields and no-result charging.

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 single parameter, domain, is already fully described in the schema with an example. The tool description does not add additional parameter semantics, so the baseline of 3 applies.

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's function: retrieving a brand's homepage top links and grouping them into Products, Categories, and Content. It adds distinctive detail (up to 10 links, per-link fields) but does not explicitly contrast itself with siblings like get_competitor_price or get_brand_snapshot.

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?

Usage can be inferred from the name and content: an agent would call this when it needs a brand's homepage link structure rather than raw competitor prices or promotions. However, the description never explicitly says when to choose this tool over the available siblings or when not to use it.

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