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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful non-annotation behavior: default exclusion of removed audiences and 'largest first' ordering. It does not state pagination behavior, response shape, or whether filters combine with AND semantics across the twelve parameters.

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 dense, front-loaded sentence with zero filler; the read marker leads and the operation follows immediately. The triple-nested parenthetical is compact but slightly harder to parse than separate clauses would be.

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 12-filter list tool with no output schema, the description covers what is listed and the default exclusion, but says nothing about the returned record shape, pagination envelope, or valid values for the status/provider/targetable filters. Adequate to start a call, not enough to predict or interpret the result.

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% for 12 parameters, so the description must compensate. It does explain include_removed, the id-or-uuid pairing for ads_account and seliee_website, and the audience type dimension (custom/lookalike/saved), but leaves search, page, per_page, ads_audience_status, ads_audience_provider, and ads_audience_targetable entirely undefined.

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 synced ad audiences') and scopes it with the audience subtypes (custom / lookalike / saved) plus the account/website id-or-uuid duality. An agent can distinguish it from list_ads_accounts, list_ads_campaigns, and list_ads_negative_lists by the resource alone, though no sibling is named explicitly.

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 only conditional guidance is 'removed ones are hidden unless include_removed', which tells the agent how to widen the result set. There is no statement of when to prefer this over sibling listing tools or what prerequisites (e.g., needing an ads account id) apply, so usage must be inferred from the name.

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