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

Annotations already indicate readOnly, idempotent, and non-destructive behavior, so the bar is lower. The description adds meaningful context beyond annotations: 'Reading is free' signals no cost for reads, and 'Rank is paid placement, not endorsement' clarifies the interpretation of results. No contradiction with annotations exists.

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 three short sentences with no filler. The primary purpose is front-loaded, and the second and third sentences add valuable interpretive context about cost and the meaning of rankings. Every sentence earns its place.

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 search tool with no output schema and no parameter descriptions, the description provides the core purpose and interpretation but leaves gaps. It does not explain what a result entry looks like, how limit interacts with the query, or whether category refines or changes the search. It is reasonably complete but not fully self-sufficient.

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 0%, so the description must compensate for parameter guidance, but it does not explicitly describe limit, query, or category. It only hints at query semantics through 'for your agent, product, brand or service.' Limit and category remain unexplained, leaving the agent to rely on parameter names alone.

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 uses a specific verb and resource: 'Find active paid advertising rankings for your agent, product, brand or service.' It clearly distinguishes this from the singular get_ranking sibling by focusing on searching multiple active paid rankings. The added context about paid placement further disambiguates the meaning of 'rankings.'

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 conveys that this tool is for finding active paid advertising rankings, which implies its primary use case. However, it does not explicitly contrast it with get_ranking or the sponsorship-related sibling tools, nor does it state when not to use it. Usage context is present but only implied.

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