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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered. The description's only added behavioral content is the categorization of audience types, which is more return-content than behavior; it says nothing about pagination, result limits, or whether inactive audiences are included.

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?

A single tight sentence with the resource stated first and no filler. The parenthetical subtype list is slightly dense but earns its place by telling the agent what audience kinds appear. Not padded, but also not maximally front-loaded with actionable detail.

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?

An output schema exists, so return values are covered, and annotations cover safety. However, with zero parameter documentation and no usage guidance, the definition leaves the two most common agent questions (what identifiers to pass, when this beats the generic list_audiences) unanswered for a 2-param tool.

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 0% and neither account_id (required) nor customer_id (optional, default "") is documented anywhere. The description never mentions these parameters, so it fails to compensate for the coverage gap; an agent must guess what customer_id does relative to account_id.

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 uses a clear verb+resource ('Lists the account's audiences') and enumerates the audience subtypes (remarketing / similar / combined), so the agent knows exactly what is returned. It does not explicitly distinguish itself from the near-identical siblings list_audiences, list_meta_audiences, or list_linkedin_audiences, relying on the tool name to carry platform differentiation.

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 trailing phrase '— for audience targeting' implies a use case but gives no when-to-use condition, no prerequisites, and no exclusion against alternatives like list_audiences or manage_audience_targeting. Usage is inferable but not stated.

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