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

With no annotations provided, the description must carry the full burden of behavioral disclosure. It states that the tool fetches and saves, implying a write operation, and clarifies the alias between adset_id and adgroup_id. It does not explicitly mention side effects like overwriting existing packs, return values, or error conditions, but the core behavior is well explained. Minor gaps prevent a 5.

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 dense but every sentence earns its place: it states purpose, the equivalence to a sibling, the Meta mirroring rationale, required parameters, and an example. It is front-loaded with the core purpose and uses a clear structure (description, requirements, example) without fluff.

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 tool's complexity (combined fetch+save, alias handling, Meta mirroring), the description covers the essential usage points. It does not mention what the tool returns or error behaviors, and there is no output schema to fill that gap. However, for the primary purpose of enabling correct invocation, it is nearly complete, missing only minor return/error details.

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%, so the description must compensate. It explicitly enumerates required parameters (advertiser_id, name) and explains that either adgroup_id or adset_id works, clarifying that adset_id is the TikTok adgroup identifier under a different wire name. The example further illustrates the expected format, fully covering parameter meaning beyond the 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 opens with a precise verb+resource statement: 'Fetch one live TikTok adgroup's interest targeting and save it as a reusable interest pack.' It clearly differentiates from the sibling interests_fetch_from_adset by noting it is equivalent to that call with a name supplied, and it explicitly references the Meta flow. The purpose is unambiguous and distinct.

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 gives explicit guidance on when to use this tool versus the alternative: 'Equivalent to calling interests_fetch_from_adset with `name` supplied, but matches the Meta two-step flow so portable agent code stays identical.' It also lists required parameters and provides a concrete example, making usage conditions clear and actionable.

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