UTM report

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

Annotations already indicate readOnlyHint=true. The description adds that the tool produces a breakdown by UTM parameters, but does not disclose additional behaviors such as pagination, result limits, or required permissions beyond what annotations provide.

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 concise sentence, front-loaded with the verb 'Breakdown', efficiently communicating core purpose. A second sentence could add parameter guidance without losing conciseness.

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?

Given the tool has 18 parameters (many undocumented) and many sibling reporting tools, the description is insufficient. It does not explain how to filter results or leverage parameters, and though an output schema exists, the description itself is too sparse to enable correct invocation without external knowledge.

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 only 22% (only 4 of 18 parameters documented). The description does not mention any parameters or explain the purpose of the many undocumented filter fields (e.g., os, tag, city, etc.), leaving the agent without guidance on how to narrow the breakdown.

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 provides a breakdown of traffic by UTM parameters (source, medium, campaign, content, term), distinguishing it from sibling reporting tools that target other dimensions. However, it does not specify the output format (e.g., counts, metrics) or whether it groups or filters by these parameters.

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 implies usage when UTM-based breakdown is desired, but it offers no explicit guidance on when to use this tool versus alternatives like report_breakdown or report_attribution, nor does it state when not to use it.

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