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

Annotations already declare destructiveHint=true and idempotentHint=false, so safety is covered. The description adds genuinely new behavioral context beyond the annotations: a dry-run/preview mode via confirm=false, which an agent would not otherwise know.

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?

Two short sentences, front-loaded with the action and the destructive object, followed immediately by the confirmation semantics. Every clause earns its place with no 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?

An output schema exists, so return values need not be explained, and annotations cover the destructive/non-idempotent profile. The preview-vs-apply detail is the key missing piece and it is present; only minor gaps remain (permission requirements, whether deletion is reversible, customer_id meaning).

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 0% across 4 parameters, so the description carries the burden. It fully explains the non-obvious 'confirm' flag but leaves customer_id (optional, defaults to empty) and the two ID parameters undocumented; the ID names are largely self-explanatory, which keeps this at baseline rather than below it.

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+resource (deletes a Microsoft audience) and clarifies the object with '(remarketing list, etc.)', which distinguishes it from delete_microsoft_campaign. It does not explicitly contrast with other delete_* siblings, but the resource is unambiguous.

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 confirm=false preview / confirm=true applies contract effectively tells the agent how to invoke it safely, but there is no explicit when-to-use guidance, no prerequisites, and no mention of alternatives such as pausing or removing targeting instead of deleting.

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