google_ads_audience_targeting_list

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

The description declares the tool is 'Read-only', which is essential. It describes the output format including fields and the resource name pattern. It also notes a cap of 1000 criteria for whole-account queries. No annotations are provided, so the description carries the full burden and does so well.

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 front-loaded with the main action and resource, then enumerates types and output fields efficiently. It uses bullet-like formatting for the types and a single sentence for usage guidance. No unnecessary words.

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 list tool with three optional parameters and no output schema, the description fully covers what the tool does, what it returns, how to scope, and the cap. It also states it is read-only. The tool's behavior is well-specified without needing annotations.

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 coverage is 100% with all three parameters described. The description adds value by explaining how to scope with ad_group_id and/or campaign_id, and the fallback to whole account when omitted. This goes beyond the basic schema descriptions.

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 clearly states the verb 'Lists' and the specific resource: audience-type criteria attached to ad groups. It enumerates the types (USER_INTEREST, USER_LIST, etc.) and the output shape, making it distinct from sibling tools like google_ads_demographic_targeting_list.

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?

It explicitly states when to use the tool: 'Use this to audit which audience segments an ad group targets or excludes before proposing targeting changes.' It also explains scoping options with ad_group_id and campaign_id, and the account-level cap. However, it does not directly compare with sibling targeting list tools or state when not to use it.

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