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

Annotations already declare readOnlyHint=true, non-destructive, and openWorld, so the safety profile is covered. The description adds that it returns id/name/status/type and parent campaign, which is useful, but says nothing about pagination, result limits, or what includeRemoved does to the result set.

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?

One compact sentence that front-loads the action and scope, then lists the output fields. No filler, no redundancy with the title.

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, the description helpfully lists the returned fields, which covers the return-value gap. But for a three-parameter read tool it omits the meaning of includeRemoved (the only parameter that changes result scope) and any pagination or result-size expectations.

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%: campaignId is documented in the schema, and the description restates that filter, but customerId and includeRemoved have no schema description and the description never mentions them. With low coverage the description needed to compensate and largely does not, leaving two of three parameters 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?

States a specific verb and resource ('List ad groups') plus the scoping dimension ('for an account, optionally filtered to one campaign') and enumerates the returned fields. This distinguishes it reasonably from write-oriented siblings like create_ad_group/update_ad_group, though it never names a read sibling such as get_campaigns to contrast with.

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 parenthetical 'optionally filtered to one campaign' implies when the campaignId path is appropriate, so usage is inferable. However there is no explicit when-to-use/when-not guidance and no mention of the alternative read tools (get_campaigns, get_ad_performance) an agent should consider instead.

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