meta_ads_insights_breakdown

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

With no annotations, the description adds value by declaring the tool read-only and listing returned metrics. It also hints at quota cost in the period parameter description. However, it could mention error handling or rate limits for completeness.

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 two paragraphs with no wasted words. The first sentence states the core purpose, then lists metrics, declares read-only, and provides usage guidance. Every sentence earns its place.

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 has 4 parameters, no output schema, and many siblings, the description covers purpose, metrics, read-only, usage guidance, and parameter details. It lacks error handling or quota specifics in the main body, but overall it is comprehensive.

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 coverage is 100%, providing a baseline of 3. The description adds meaning beyond the schema by explaining account_id format, campaign_id, breakdown combinations, and period syntax including explicit range and quota cost, adding significant value.

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 the verb 'pulls' and the resource 'delivery metrics for a campaign broken down along one dimension'. It lists the returned metrics and explicitly distinguishes from siblings by naming alternative tools (meta_ads_analysis_audience, meta_ads_analysis_placements) for pre-packaged splits.

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 explicit guidance: 'Use this for ad-hoc slicing; for pre-packaged splits use the dedicated ... tools'. This clearly tells the agent when to choose this tool over alternatives.

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