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

Goes well beyond the annotations by disclosing that the tool runs a Google validate-only pass, captures a complete affected-resource snapshot, stores a private draft, and does not transmit the change. That behavior (a prepare/draft that is non-destructive but writes state, consistent with readOnlyHint=false and destructiveHint=false) is not inferable from the structured fields.

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?

Three sentences, front-loaded with purpose, then behavior, then the required follow-up step. Every sentence adds information; no filler or restatement of the tool name.

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?

With no output schema and a nested body object, the description still conveys what the tool produces (a private draft plus snapshot) and the required downstream call. The main remaining gap is the undocumented field_type enum, which the agent must infer from the schema alone.

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 description coverage is only 33% (just customer_id), and the description adds no parameter-level meaning. The nested body fields asset_group_id, asset_id, and especially field_type (an enum of link types) are never explained in prose, so the description does not compensate for the coverage gap.

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?

States a specific verb and resource: prepare removal of an existing asset link from a Performance Max asset group. It is clearly distinguishable from the sibling google_ads_asset_group_link_prepare (adds vs removes) and google_ads_asset_unlink_prepare (asset-group level vs asset level). No tautology.

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?

Explicitly states the workflow: prepare a draft, show it for approval, then call google_ads_asset_group_unlink_confirm. The named alternative and the gating condition are clear, though it never states when NOT to choose this over the plain asset-level unlink prepare.

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