google_ads_assets_upload_image

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

With no annotations present, the description fully carries the behavioral transparency burden. It discloses the mutating nature ('creates a new Asset row'), the lack of a delete tool, validation limits (5 MB, file extensions), the side effect of reading from local filesystem and POSTing bytes, and the exact return shape. This is comprehensive and goes well beyond minimal expectations.

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 well-structured and front-loaded with the core purpose. Each sentence adds distinct value: return values, mutation caveat, validation, side effects, and follow-up tool. Despite being somewhat long, there is no wasted or redundant content.

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 has moderate complexity (file upload, validation, mutation, no deletion, local filesystem read) and no output schema. The description covers return values, side effects, constraints, and the next step to take. This is a complete picture for an agent to select and invoke the tool correctly.

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 input schema already provides descriptive text for all three parameters (100% coverage), so the baseline is 3. The description adds meaningful context beyond the schema by explaining the return format, default behavior for `name` (basename), and the credential fallback for `customer_id`. This elevation to 4 is warranted.

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 uses a specific verb ('Upload') with a clear resource ('local image file to Google Ads as an image Asset') and states its intended use ('for use in Responsive Display Ads or image extensions'). It is easily distinguished from sibling tools like google_ads_image_assets_list (listing) or meta_ads_creatives_upload_image (Meta platform).

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 provides clear contextual guidance: it notes the asset is for RDA/image extensions and directs the user to google_ads_ads_create_display for the next step. It doesn't explicitly state when not to use this tool versus other upload tools, but the mention of the no-delete limitation and the recommended follow-up gives practical usage direction.

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