direct_attach_video_extension

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

With no annotations, the description carries the burden of behavioral disclosure. It does state that this is a write operation and that allow_write=true is needed to actually mutate live cabinets, plus mentions optional moderation. However, it omits side effects, permission requirements beyond allow_write, behavior when creative_id is reused or invalid, error handling, and whether the operation is idempotent.

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, compact sentence that front-loads the 'WRITE' signal and packs essential workflow steps into minimal words. Every phrase earns its place, but the density makes it cryptic; a slightly more structured or plain-language version would improve readability without bloating the text.

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?

For a mutation tool with 7 parameters, no output schema, and no annotations, the description is insufficiently complete. It does not describe return values, how multiple ad_ids are handled, failure modes, or why project is restricted for writes. This leaves an agent uncertain about critical behaviors when invoking the 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?

Schema coverage is low at 43%, so the description must compensate. It adds value by showing that video_id is used in creatives.add, creative_id allows skipping creative creation, and moderate_after is optional. However, it does not clarify ad_ids, dry_run, or the project key restriction, leaving significant gaps for those parameters.

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 identifies the tool as a write operation that attaches a video extension by creating a VideoExtensionCreative and updating ads with the creative ID. This distinguishes it from sibling tools like direct_upload_advideo, which only uploads videos. However, the use of internal API call names (creatives.add, ads.update) makes the purpose less immediately accessible to someone unfamiliar with the API.

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 no explicit guidance on when to use this tool versus alternatives such as direct_attach_callouts or direct_upload_advideo. It only notes the write nature and allow_write=true requirement, leaving the agent to infer appropriate use from the tool name and sibling list.

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