meta_ads_analysis_cost

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

Declares read-only operation, describes the decomposition output with per-driver magnitude and action hint, and notes that longer windows cost more Graph API quota. No annotations are provided, so this is adequate.

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?

Three sentences covering purpose, behavioral note, and usage guidance without any redundant text. Efficient and well-structured.

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?

No output schema exists, but the description adequately explains the return value (decomposition with driver magnitudes and action hints). Does not mention error cases or prerequisites, but for a diagnostics tool this is sufficient given the other details.

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?

Input schema has 100% coverage with detailed descriptions for each parameter. The description adds marginal value by clarifying the period cost implication but does not significantly enhance beyond the 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 clearly states the tool diagnoses root causes of rising spend or degrading CPA on a Meta Ads campaign, listing specific drivers (bid increase, CPM inflation, etc.) and outputs per-driver magnitude and action hint. It differentiates from sibling analysis tools by noting it separates auction-side from creative-side causes in one call.

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?

Explicitly says 'Use this when the operator reports why did CPA jump', providing a clear context. Does not explicitly mention when not to use it or alternatives, but the stated use case is specific and sufficient.

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