add_image_assets

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

With no annotations, the description carries the behavioral burden and handles it well. It discloses the dry-run behavior unless confirm=true, local validation based on field_type, size and aspect-ratio constraints, and Google's DUPLICATE_ASSET rejection behavior.

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 long but information-dense, with every sentence earning its place. It front-loads the core purpose, then provides precise format examples, validation requirements, duplicate handling, and the confirmation flag without filler.

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 tool with no annotations and no schema-level descriptions, this definition is complete: it covers input shapes, accepted file types and dimensions, field_type semantics, duplicate-asset handling, and dry-run behavior. An output schema exists, so return-value details are not required from the description.

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 0%, and the description substantially compensates by documenting the exact images array structure, valid field_type values, optional name, and the asset_resource_name alternative. It also explains confirm as dry-run unless true; customer_id and campaign_id are left to their self-explanatory names and the surrounding campaign context.

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 opening sentence states a specific verb and resource: 'Upload image files as image assets and attach them to a Search campaign as AD_IMAGE.' It also distinguishes Search's AD_IMAGE link type from Performance Max and Display field types, which helps separate this tool from sibling asset tools.

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 clearly establishes the Search-campaign context and explains when to use an existing asset_resource_name versus uploading a file, including the duplicate-asset case. It does not explicitly name sibling tools as alternatives, but it gives enough contextual guidance to route usage.

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