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

The description discloses write classification, synchronous execution, mutation modes, partial failure policy, idempotency behavior, and seat requirements. It goes well beyond the annotations (readOnlyHint false, idempotentHint true) by explaining the derived retry key and seat authorization rule.

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 excessively long and includes generic response-handling instructions (e.g., never display raw JSON, use assistantSummary first) that are not specific to this tool. The first part is concise, but the appended meta-information makes it bloated.

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 is complex with nested structures, mutation modes, and idempotency concerns. The description covers these aspects well, including failure policy and seat requirements, and with an output schema present, return-value explanations are not needed. Some details like the meaning of validate_only vs execute could be expanded, but overall it is 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?

With 0% schema description coverage, the description adds useful mappings for campaignName, funnelStage, targetImpressions, and primaryKpi/secondaryKpi. However, it does not explain many other parameters such as budget, status, dates, or the sizes arrays, leaving gaps in understanding.

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 creates a Studio campaign with a specific verb and resource. It also clarifies that all fields go inside the campaign object and provides natural-language mappings, distinguishing it from sibling tools like update_campaign.

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 gives clear context for creating a new campaign, including mapping natural language terms to fields and structural guidance ('Put all campaign fields inside campaign'). It also notes seat requirements for writes, but does not explicitly name alternative tools for other operations.

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