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

Annotations already declare the tool is not read-only, not destructive, and not open-world. The description adds useful context beyond that: it creates a draft (not a launched campaign) and returns the draft campaign and channel configuration or validation errors, which helps set expectations for side effects and responses.

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 four short sentences, front-loaded with the core action and resource. Every sentence contributes value: structure name, container grouping, return behavior, and the draft-only caveat.

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 complexity and the very rich input schema, the description covers what the tool does and what it returns. It could mention prerequisites such as needing existing ads/offers or connected channels, but those details are already in the schema descriptions.

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?

The schema has 100% description coverage and is extremely detailed, so the baseline is 3. The description only summarizes that audiences, ads, and offers are grouped within channel-specific containers, adding little beyond what the nested schema already explains.

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 states a specific verb (Create), resource (draft campaign), and structure type (Channel First / Native Structure N×N×N). It distinguishes this tool from the generic create_campaign and from launch_campaign by explicitly noting 'This tool does not launch it.'

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?

Usage is implied: use this tool to create a draft campaign with native structure, as opposed to launching one. However, it does not explicitly state when to choose this over sibling tools like create_campaign or add_and_edit_native_campaign_elements, nor does it name the alternative for launching beyond the exclusion.

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