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

Annotations already declare the tool read-only and non-destructive, and the description adds meaningful behavioral context: what set of brands is included, how they are ranked, and the supported time windows. It does not disclose output structure or pagination, but those are not critical given the read-only, list-style nature.

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, well-structured sentence that front-loads the core result set and ranking logic. Every part adds relevant information without redundancy or 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 read-only list tool with three optional parameters and no output schema, the description covers the essential semantics: what is returned, how it is ranked, which periods are supported, and the optional category filter. It does not describe the exact response shape, but the absence of an output schema and the simple list nature make this less critical.

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?

With schema coverage at 67%, the description partially compensates by explaining that period maps to 7 days/30 days/year and that category is an optional filter. The limit parameter is not mentioned in the description, but the schema already documents its default and bounds.

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 identifies the resource (brands that held a slot when it closed plus the current live-slot leader) and the specific action (list them ranked by what they paid). It also distinguishes the tool from siblings like get_board and get_stats by describing a winners-oriented read operation.

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: when you need past and live slot winners over a chosen period, optionally filtered by category. However, it gives no explicit guidance about when not to use it or how it compares to sibling tools such as get_stats or get_brand_stats.

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