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

Annotations already declare readOnlyHint/idempotent/non-destructive, so safety is covered. The description adds real value beyond them: the default window is the last 30 days, the span can be overridden, and it discloses what the response contains (including suggested negative keywords and PMax categories) — notable since there is no output schema.

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 scope is front-loaded ('Google Ads search terms over the last 30 days') and the trailing enumeration is dense but each item conveys distinct retrievable content. The single run-on paragraph with a long comma list is slightly heavy, keeping it from a 5.

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 carries the burden of describing returns and does so thoroughly, and it documents the optional date-window override and its default. An agent has everything needed to call it correctly and interpret the result.

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 the schema already documents both `from` and `to` with the 'send together or omit both' rule. The description restates that same constraint ('both or neither') without adding format or edge-case detail, so it is a baseline 3.

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 names a specific resource (Google Ads search terms over the last 30 days) and enumerates the concrete outputs: brand vs non-brand split, per-campaign brand share, no-conversion spend, suggested negatives, converting terms, and PMax search categories. It is unmistakably distinct from siblings like get_google_product_split or get_product_performance.

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 gives explicit when-to-use triggers ('any question about search terms, negative keywords, wasted Google search spend, brand vs non-brand, or brand inflating a campaign's ROAS'), which is strong context. It stops short of naming alternatives or when-not-to-use conditions, so it falls short of a 5.

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