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

Annotations declare destructiveHint=true and idempotentHint=true, and the description adds the crucial non-annotated behavior: the call is a no-op preview unless confirm is true. It still does not say what a preview returns, what errors look like, or what REMOVED implies for reporting history.

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 short sentences, zero filler, and the primary action is front-loaded ahead of the identifier-sourcing and confirmation details.

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 4-required-param mutation with no output schema and thin schema coverage, the description covers the essentials: what changes, what is needed, and that nothing happens until confirmed. Missing only return/error expectations and whether repeated calls are safe, which the idempotentHint partly signals.

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 20% (confirm alone), so the description must compensate. It does add real value by naming the source resource for ad_group_id/ad_id, but customer_id and status carry no extra explanation beyond the enum, so it only partially closes the 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 set on a specific resource: 'Pause, enable or remove one ad.' The scope word 'one ad' plus the ad_group_id/ad_id pairing clearly separates it from ads_set_campaign_status, ads_set_keyword_status and ads_create_ad.

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 tells the agent where the required identifiers come from ('Get ad_group_id and ad_id from an ads_report query on the ad_group_ad resource') and states the default preview gate. It does not name an alternative for the case where you want to edit the ad creative rather than its status, so no true when-not guidance.

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