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

With no annotations, the description carries the burden. It does disclose a useful behavioral requirement—the same base64 data must be resubmitted—which is not obvious from the schema. However, it doesn't state side effects, idempotency, or what response/receipt to expect, so transparency is only partial.

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?

A single front-loaded sentence with no filler; every phrase ('Confirm', 'image asset upload', 'same base64 image data') carries semantic weight.

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?

No annotations, no output schema, and no guidance about the prerequisite draft from google_ads_asset_upload_prepare or what happens after confirmation. For a required-4-param mutation tool, the description leaves too much for the agent to infer from sibling names.

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 only 25% (customer_id only). The description adds meaning to base64_data (must be the exact same data) and narrows content_type to image, but draft_id's role and content_type's accepted format or values remain undocumented. It partially compensates for the low schema coverage.

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 names the verb ('Confirm'), the resource ('image asset upload'), and the required mode ('resubmitting the same base64 image data'). By specifying 'image' it distinguishes this from video upload confirmation, and 'confirm' separates it from the prepare variant.

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 confirmation workflow is implied by the word 'confirm' and by the prepare/confirm sibling pattern, but the description never explicitly says to call this after google_ads_asset_upload_prepare or identifies conditions/alternatives. There is also no guidance for when not to use it.

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