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

No annotations are provided, so the description carries the full burden of behavioral disclosure. 'List' implies a safe read operation, but the description does not address pagination, result limits, permissions, or what data is returned, leaving most behavioral traits unspecified.

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 single sentence is front-loaded and free of waste. It is appropriately sized, though it is arguably too terse to serve as a complete tool definition.

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?

This is a simple read operation with a fully documented three-parameter schema, so the description covers the core action. However, without annotations or an output schema, it should do more to explain return behavior or filtering semantics.

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 campaign_id and the optional ad_group_list_query filter. The description adds no parameter-level meaning beyond what the schema provides, making the baseline of 3 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 clear verb (List) and resource (ad groups) scoped to a campaign, which distinguishes it from mutation siblings like create_ad_group and update_ad_group. It does not explicitly contrast with list_campaigns or list_ad_group_reports, but the resource is specific enough to infer.

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?

Usage is implied by the scoping phrase 'in a campaign,' so an agent can infer it is used when ad groups for a known campaign are needed. However, the description gives no explicit when-to-use guidance, prerequisites, or alternatives such as list_campaigns or search_apps.

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