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

The description adds significant context beyond the annotations: budget in cents (5000 = $50), campaign budget optimization constraint (ad sets must not carry budget if campaign budget is set), and the option to leave budget empty for per-ad-set budgeting. These are behavioral traits not captured by annotations. However, it does not disclose other behaviors such as required permissions or rate limits, but the provided details are valuable.

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 concise and well-structured: a list of actions with a one-line purpose each, followed by critical notes on objectives, budgets, and deletion. It is front-loaded with the clear purpose and actions, and every sentence contributes meaningful information without verbosity.

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 complexity (11 params, multiple actions) and lack of output schema, the description is fairly complete: it covers all actions, objectives, budget nuances, and bulk support. It misses some parameter detail (e.g., bid_strategy, special_ad_categories), but the core semantics are addressed. It also provides a cross-reference to the delete tool, enhancing contextual completeness. A score of 4 is appropriate, as some parameter semantics remain undocumented.

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 schema has 11 parameters with 0% description coverage, so the description must compensate. It explains the semantics of 'budget' (daily_budget and lifetime_budget implicitly) in cents and the CBO relationship, and enumerates the objective enum values. It also mentions 'name' and 'status' when describing create and update actions, helping to map parameters to actions. The description does not cover all parameters but addresses the most critical semantics.

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 can create, update, pause, or activate Meta Ads campaigns, and names the specific actions. It distinguishes itself from siblings by noting the flattened action 'pause' and pointing to meta_ads_campaign_delete for destructive deletes, and is clearly differentiated from the sibling write tools like meta_ads_campaign_write_create and meta_ads_campaign_write_update.

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?

It provides clear context on when to use it for campaign management actions and when not to (for destructive delete). It also mentions bulk support and clarifies budget handling, but does not explicitly exclude other similar write tools by name, though the action list and reference to delete tool provide adequate guidance.

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