Create Ad Set

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

Annotations already signal a mutating, non-idempotent, non-destructive operation, so the description is not required to restate that. It adds useful behavioral detail: budget values are in cents, lifetime_budget depends on end_time, placement_soft_opt_out can still use up to 5% of spend, and the call returns the new ad set ID. No auth or rate-limit specifics are included, but the description exceeds what annotations alone provide.

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 tool purpose is front-loaded in one sentence, followed by a tight Args list and a one-line return value. For a 13-parameter operation with a nested targeting object, the length is justified and every line provides a constraint, example, or default.

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 complex create operation with 13 parameters, a nested targeting object, and no output schema, the description covers the required identifiers, budget rules, enums, defaults, and the return ID. The targeting example and dependency constraints are exactly the kind of context an agent needs that is not available in the schema alone.

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 Args section substantially enriches the schema, which only has 54% description coverage. It adds units ('in cents'), a concrete targeting JSON example, ISO 8601 format for timestamps, the lifetime_budget/end_time dependency, explicit enum examples, and the PAUSED default. The only parameter not mentioned in the description is response_format, which is already fully documented in the input 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 'Creates a new ad set within a campaign', giving a specific verb, resource, and parent scope. This separates it from sibling creation tools like meta_create_campaign, meta_create_ad, and the update counterpart meta_update_adset even though none are named.

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 purpose statement clearly establishes when to use it: when a new ad set must be created inside a campaign. However, it does not explicitly list alternatives or state when not to use it, so it stops short of full routing guidance.

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