get_campaign_performance

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds useful context like configurable date ranges and a row limit, but it does not disclose the return format, metric fields, aggregation, or any potential quirks for a metrics-reporting tool.

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 front-loaded with a clear one-sentence purpose, followed by a compact and structured Args list. Every line adds necessary semantic information that the schema does not provide, with no filler or repetition.

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?

All required parameters are explained in enough detail for a knowledgeable agent to invoke the tool. However, with no output schema, the description does not state which campaign performance metrics are returned or what the response rows look like, leaving a meaningful gap for interpreting results.

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 0%, so the description carries the full burden for parameter meaning. It documents all five parameters clearly, including predefined and custom date-range formats, acceptable status filter values, and the default limit.

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 opens with a specific verb and resource: 'Get campaign performance metrics over a date range.' This clearly identifies the operation and distinguishes it from sibling tools like get_campaign, get_ad_group_performance, or get_account_performance_summary.

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 tool's intended use is implied by the name and description—campaign-level performance reporting—but there is no explicit guidance about when to choose it over alternatives such as get_campaign or get_keyword_performance. No exclusions or selection conditions are stated.

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