meta_ads_analysis_compare_ads

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

With no annotations, the description carries full burden. It declares 'Read-only', explains the output structure (rows with metrics, relative-score, verdict), and notes that longer period windows cost more Graph API quota. This provides sufficient behavioral insight without contradictions.

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 efficiently cover purpose, output details, and usage guidance. No redundant information; front-loaded with the core action. 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's complexity, the description covers all essential aspects: purpose, what it returns, how to use it, and ties to a sibling. No output schema but the output is described clearly. Cost implications are noted, making it complete for an analysis tool.

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% description coverage. The description adds extra value by reinforcing that comparison is within a single ad set and highlighting the quota cost for the period parameter, which goes 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 'Runs an A/B-style comparison of ads inside a single ad set', specifying the verb 'comparison' and the resource 'ads' within a single ad set. It distinguishes from siblings like meta_ads_analysis_performance and meta_ads_split_tests_* by emphasizing the intra-ad-set scope and statistical ranking.

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 states 'Use this to decide which creatives to pause' and suggests pairing with meta_ads_ads_pause. It provides clear context for when to use, though it does not explicitly mention when not to use. Still, the guidance is practical and actionable.

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