gads_campaign_performance

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

With no annotations, the description carries the full burden of behavioral disclosure. It only states the action and metrics, omitting details about return structure, pagination, default sorting, freshness, or authentication. The description adds minimal context beyond the basic 'get' intent.

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 a single sentence that directly communicates the tool's function and the key metrics. Every word earns its place, and there is no redundant or irrelevant information.

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 tool has no output schema and no annotations, so the description should clarify the return shape and usage context. It names the metrics but does not explicitly state that results are per campaign or grouped, nor does it mention the impact of filters. This is adequate for a simple read tool but leaves gaps for a new user.

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?

Input schema covers 100% of parameters with descriptions, so the baseline is 3. The tool description adds value by listing the metrics returned, but it does not elaborate on how parameters like orderBy or dateRange affect results. It neither compensates for nor detracts from the schema.

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 tool retrieves performance metrics for Google Ads campaigns and enumerates specific metrics (impressions, clicks, cost, conversions, CTR, CPC, conversion rate). While it doesn't explicitly contrast with sibling tools like keyword or ad group performance, the noun 'campaigns' is specific enough to distinguish the resource.

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?

No guidance is provided on when to use this tool versus the many sibling tools (e.g., gads_keyword_performance, gads_ad_group_performance). It lacks context about data ranges, prerequisite setup, or scenarios where campaign-level metrics are appropriate.

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