meta_ads_audiences_create

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

No annotations are provided, so the description carries the full burden. It discloses that the tool is mutating and reversible via rollback_apply (which deletes the audience). It also explains the behavior of different subtypes: WEBSITE auto-generates rule if omitted, CUSTOM requires explicit rule or upload. It mentions retention_days limits (1-180, default 30).

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 a single paragraph but is reasonably concise and front-loaded with the tool's purpose. It covers key points without unnecessary verbosity. However, it could be structured more clearly (e.g., separating subtype details).

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 complexity (8 parameters, nested rule object, subtypes, compliance requirements), the description covers most aspects: output (returns audience_id), reversibility, subtype behavior, and links to lookalike. No output schema is present, so the description explains the return value. It is fairly complete for a mutation 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?

The input schema has 100% description coverage. The description adds context beyond the schema by explaining that rule can be auto-generated for WEBSITE, that customer_file_source is for compliance, that pixel_id can be found via meta_ads.pixels.list, and that account_id requires 'act_' prefix. This adds meaningful value.

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 creates a Custom Audience in a Meta Ads account and returns the audience_id. It explains the subtypes (WEBSITE vs CUSTOM) and distinguishes from the sibling tool meta_ads_audiences_create_lookalike by mentioning it is for similarity-expanded reach.

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 provides guidance on when to use this tool vs alternatives, such as using meta_ads_audiences_create_lookalike for similarity-expanded reach. It also explains when to use WEBSITE vs CUSTOM subtypes. However, it does not explicitly mention when not to use this tool (e.g., for listing audiences).

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