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

The description goes far beyond the annotations by disclosing critical operational behaviors: the dependency on external APIs (Ahref's), the use of agency usage limits, and the guarantee that the output will report the cost of the call. This provides a high level of behavioral transparency.

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 packed with necessary information in a single, dense paragraph. While it is functional, breaking the operational details (costs, APIs) into bullet points would enhance scannability and structure.

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?

The definition is extremely complete for a data-fetching tool. It covers not just the metrics, but the entire operational lifecycle: data source, cost, and required behavior (like linking to Ahref's).

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?

Since the schema coverage is 100%, the description's role is largely informational. It does not add technical semantic meaning beyond what the schema already covers, but it provides appropriate context regarding the tool's scope.

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 is highly specific, listing exactly what is analyzed: keywords in the top 100, estimated monthly organic visits, and specific keyword positioning (1-10, 2-3, 4-10). This provides maximum clarity on the tool's function.

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?

It provides excellent operational usage guidance by explaining the three possible data sources (DataForSEO, Ahref's, or both) and differentiating between paid external calls and free internal copy requests. This context informs when the agent should expect costly external results versus immediate internal ones.

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