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

Annotations declare readOnlyHint=false (a write) but destructiveHint=false, so the safety profile is already given. The description usefully adds that confirmation requires re-sending identical data, implying an idempotency/verification check, but says nothing about failure behavior on a payload mismatch.

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 zero filler; the confirmation mechanism is stated first and no redundant restatement of the name or title is present.

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 confirm step with no output schema and annotations covering safety, the description covers the core mechanic but omits the link to the prepare step and the draft_id it generates, leaving the agent to infer the workflow.

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 20% (customer_id alone is documented), so the description must carry more weight. It does clarify the semantics of base64_data (must be the same data) and the gdrive: prefix for selection_key, but draft_id and content_type remain entirely unexplained.

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?

Clear specific verb ('Confirm') and resource ('image asset upload'), and it names the exact payload mechanism needed (same base64 data or same gdrive: selection_key). It reads clearly as the second half of the prepare/confirm pair with google_ads_asset_upload_prepare, though it never names that sibling explicitly.

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 'resubmitting the same base64 image data or the same gdrive: selection_key' clause is real guidance on how to invoke it, but there is no statement of when to call this versus the prepare step, what happens if the data differs, or any precondition tied to draft_id.

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