Create Campaign

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

Annotations already convey a write operation via readOnlyHint=false and non-idempotent behavior via idempotentHint=false. The description adds useful constraints like 'lifetime_budget requires stop_time' and 'Returns the new campaign ID.' However, it doesn't mention permissions, potential side effects (e.g., ad spend), or error cases, so it adds only moderate behavioral context beyond the annotations.

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 well-organized: a one-line purpose, a scannable Args list, a targeted note about Advantage+ migration, and a return value statement. It is slightly redundant with the schema's parameter descriptions, but there is no fluff and the key usage note is prominent.

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 9-parameter create tool with no output schema, the description covers all parameters, explains special requirements, states the return value, and includes the relevant Advantage+ alternate path. Minor gaps remain around permissions, error conditions, and the relationship between budgets, but overall an agent has what it needs to call this correctly.

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 89%, so the schema already documents most parameters. The description adds meaning by explaining that special_ad_categories is required for housing, employment, and credit ads, and explicitly connects lifetime_budget to stop_time. This goes beyond the schema's basic 'compliance' label.

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 campaign in a Meta ad account,' which is a specific verb and resource with clear scope. This immediately distinguishes it from sibling tools like meta_get_campaign, meta_update_campaign, and meta_delete_campaign.

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 an explicit usage path for OUTCOME_SALES: create a standard campaign first, then use meta_migrate_campaign_to_advantage_plus to convert to Advantage+. This is a concrete when-to-use/alternative routing. It doesn't broadly contrast against adset/ad creation tools, but the guidance is clear for the main alternative.

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