list_third_party_audience_layers

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

No annotations are provided, so the description carries the burden. It discloses that results include CPM premium estimates and performance notes, adding value beyond a simple list. However, it does not mention safety (e.g., read-only nature) or authorization needs.

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?

Two concise sentences with no extraneous information. The first sentence states the core function, and the second clarifies filters and additional content. It is front-loaded and efficient.

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 the lack of output schema and annotations, the description adequately covers what the tool returns: a list of segments/layers with CPM estimates and performance notes. It is sufficiently complete for an agent to understand the tool's purpose and output.

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?

The schema has 0% description coverage on its 3 optional parameters. The description explicitly maps each parameter purpose: 'Filter by platform, default use, or best-performing flag' directly corresponds to platform, defaults_only, and best_performers_only, respectively. This significantly adds meaning beyond the bare schema.

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 it lists third-party audience segments and layers used as targeting overlays, with optional filters. This verb+resource combination is specific and distinguishes it from related tools like list_first_party_audiences.

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 mentions filtering by platform, defaults, or best-performing, which gives usage hints. However, it does not provide explicit guidance on when to choose this tool over alternatives or 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.