create_video_ad

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

Annotations already indicate a non-read-only, non-idempotent mutation. The description adds concrete creation behavior, the Video-campaign constraint, default status ENABLED, and meaningful ad_format differences (skippable, 6-sec non-skip, in-feed). It does not disclose permissions, failure modes, or return payload, so it is not fully transparent.

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 one-sentence purpose is front-loaded, followed by a clean one-line-per-parameter list. Every parameter is covered without prose padding or redundant narrative.

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 no output schema and 10 parameters, the description covers all input semantics and the critical campaign-type constraint. It omits the return shape or created-ad resource name, which is a minor but real gap for a creation tool.

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 provides no property descriptions, but the Args block fully compensates by documenting all 10 parameters. It includes an example YouTube ID, CTA examples, expansion of ad_format options, defaults, and optional/required distinctions.

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?

Description opens with 'Create a Video ad for Video campaigns (YouTube)', giving a specific verb, resource, and channel. It clearly differentiates from sibling ad-creation tools like create_responsive_search_ad and create_demand_gen_ad by scoping to Video campaigns.

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?

States the key prerequisite that ad_group_id must be in a Video campaign, and documents defaults for status and ad_format. It does not explicitly name alternatives or when-not-to-use conditions, but the Video-campaign scoping gives clear selection context.

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