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

Annotations provide readOnlyHint=true, so safety is covered. The description adds valuable behavioral context: US search data only, domain preferred over company name, and the exact metrics returned (volume, CPC, position, landing URL, share, totals). This goes beyond what annotations state, though it does not mention rate limits or data freshness.

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?

Two dense sentences front-load the core output, then provide usage guidance and input constraints. No wasted words, though the first sentence is long and packed with many data fields.

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?

With no output schema, the description enumerates return fields in sufficient detail for an agent to know what to expect. Pagination behavior is not described, but the limit parameter covers that need.

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%, so the schema already documents all parameters. The description's note about domain preference is already present in the schema, so it adds no additional parameter meaning beyond what structured data provides.

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 specific resource: search keywords a website buys ads on (paid) and ranks for organically, with detailed data fields. It is easily distinguishable from sibling tools like get_domain_info and get_domain_value by the keyword focus and the explicit output metrics.

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 includes an explicit 'Use this when...' clause enumerating user intents: keywords bought/bid on, ad spend, rankings, and competitor comparison. It lacks a when-not clause or named alternatives, but the guidance is concrete and actionable.

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