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

Annotations already declare this as a safe, read-only, idempotent operation, so the bar is lower. The description adds some useful behavioral context by noting that large portals are listed apart and by summarizing the metrics included, but it does not disclose ordering, pagination, or other operational details beyond what annotations already cover.

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 compact and front-loads the core definition of the returned sites and their metrics. The second sentence about large portals is short and relevant, though the overall phrasing is more noun-phrase summary than actionable instruction.

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 simple read-only tool with a fully described single optional parameter, rich annotations, and an output schema, the description provides enough context to understand what data is returned. The main remaining gap is selection guidance against related sibling tools, which is only partially addressed.

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%, and the single optional 'site' parameter is fully explained in the schema, including its fallback behavior when omitted. The description adds no additional parameter meaning, so the baseline of 3 is 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?

The description clearly identifies the resource as sites ranking on Google for the same searches as the user, and lists the specific fields returned: keywords in common, size, and count of tracked keywords ranked above. It does not, however, differentiate itself from the sibling tool get_competitors, leaving ambiguity about which competitor tool to select.

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 the tool is for viewing Google competitors, but it gives no explicit guidance on when to use it versus alternatives such as get_competitors, get_google_overview, or get_google_rankings. It also provides no when-not conditions or prerequisites.

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