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

Annotations already declare destructiveHint=true and readOnlyHint=false, but the description adds a useful live-account warning and highlights the confirm:true safety gate. It does not explain whether unspecified fields are preserved or what the response contains, but the added safety context is meaningful.

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?

The description is compact and front-loaded with the most important warning — that this is a write operation affecting the live account — followed by the required confirm gate and the updatable fields. Every clause earns its place.

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?

Given full schema coverage and destructive annotations, the description supplies the essential safety gate and field scope. It is complete enough to invoke correctly; only minor edge-case details like preservation of unmentioned fields are absent, and no output schema exists so return-value explanation is not required.

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 100%, so the schema already documents all six parameters including customer_id and ad_group_id. The description reinforces the updatable fields and MICROS unit but adds little meaning beyond what the schema provides; baseline 3 is appropriate.

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 states a specific verb and resource — update a Google Ads ad group — and names the updatable fields (name, status, max CPC bid). It is clear what the tool does, but it does not differentiate itself from siblings like google_ads_set_status or google_ads_update_campaign.

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 description makes clear this is for updating an existing ad group's name, status, or bid and that confirm:true is required. However, it provides no explicit when-not guidance or routing to alternatives such as google_ads_set_status, google_ads_update_campaign, or google_ads_get_ad_group.

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