ads_search_terms

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

No annotations are present, so the description carries the full burden. It explicitly states 'read-only' and discloses an important data behavior: 'Google withholds terms too few people searched, so an absent term is unknown rather than absent'. This adds meaningful context beyond the tool name. It does not mention authentication, rate limits, or pagination, but the output schema covers return format, so this is sufficient.

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 two sentences with no filler. The core purpose and the key behavioral caveat are front-loaded, and the read-only note is appended efficiently. 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 read-only tool with a clear output schema and four optional parameters, the description covers the essential context: what data it returns, the comparison to organic queries, and the data withholding nuance. It doesn't explain prerequisites like authentication or campaign selection, but these are likely common across the toolset and not critical for this simple read operation.

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 coverage is 100% and each parameter has a descriptive explanation (e.g., 'Drop search terms below this many impressions'). The main description does not add additional meaning about parameters beyond what the schema already provides, so it meets the baseline but does not exceed it.

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 ('Read') and identifies the exact resource ('queries that actually triggered an ad') and the data returned (keyword and metrics). It also distinguishes itself from the organic equivalent by calling itself the 'paid equivalent of the Search Console query dimension', which helps an agent separate it from sibling tools like search_analytics. This is a clear, specific purpose statement.

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 provides a useful comparison to Search Console but does not explicitly name alternative tools or state when not to use this one. It implies this is for paid search queries, but an agent would need to infer that organic queries belong elsewhere. There is no explicit routing to sibling tools like ads_keywords or search_analytics, leaving some ambiguity.

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