get_campaign_performance

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

The description identifies the operation as a 'get' implying read-only, but with no annotations, the agent must infer safety. It does not mention pagination, rate limits, or whether results are cached. However, the limit parameter is described in the schema, and output schema likely details the metrics.

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 exceptionally concise at 11 words, front-loading the verb 'Get' and the resource 'campaign performance metrics', followed by constraints. Every word earns its place. No wasted sentences or redundancies.

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 a simple purpose and a schema that covers all parameters. The output schema presumably describes the return structure. The description suffices for understanding the basic function, but it omits contextual details such as the maximum date range or what specific metrics are returned. Given the presence of an output schema and complete input schema, the description is adequate but not comprehensive.

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?

All four parameters are fully described in the input schema (100% coverage). The tool description does not provide any additional explanation of parameter meaning or usage beyond what is already in the schema. The mention of 'date range' and 'ordered by cost descending' pertains to the overall operation, not parameter semantics.

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 action (get), resource (campaign performance metrics), scope (date range), and ordering (cost descending). This distinguishes it from sibling tools like get_campaigns (which likely returns campaign metadata) and get_ad_groups (different 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?

The description provides no explicit guidance on when to use this tool versus alternatives like get_campaigns or get_ad_groups. It does not mention scenarios where this tool is preferred or excluded.

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