Build a full Meta ad (campaign → ad set → ad, paused)

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

The description discloses that all are created PAUSED and spend nothing until activated, which adds behavioral insight beyond the annotations (which only indicate non-readonly, non-idempotent, non-destructive). It also notes the limitation to IMAGE ads, but does not cover all potential side effects (e.g., idempotency is false, but no mention of duplicate creation risk). Annotations already provide a baseline, and the description adds valuable context.

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 appropriately short (3 sentences), front-loaded with the core purpose and state, and uses clear, direct language. Every sentence adds essential information with no redundancy.

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 (13 parameters, output schema exists), the description covers the overall workflow, state (paused), prerequisites, required inputs, limitations, and where to get required IDs. It also references the activation tool. The output schema likely handles return details, so the description is sufficiently complete.

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 100%, so baseline is 3. The description adds value by clarifying that adAccountId comes from list_meta_pages, and that dailyBudget spends only when ACTIVE. It also explains the relationship between imageUrl and imageUrls (one ad each). This goes beyond the schema descriptions.

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 builds a complete Meta ad structure (campaign → ad set → ad) from image creatives, distinguishing it from siblings like create_meta_campaign or set_meta_campaign_status. The verb 'Build' and resource 'full Meta ad' are specific and unambiguous.

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 clear usage context: it is the path to create a campaign and put ads on it, and mentions prerequisites like adAccountId from list_meta_pages, and that it's IMAGE ads only. It hints at alternatives (set_meta_campaign_status to activate) but could explicitly state when not to use this tool in favor of siblings like create_meta_campaign.

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