meta_ads_analysis_performance

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

Declares the tool as read-only, which is critical for transparency. Describes the output structure (current/prior metrics, delta %, callouts). However, with no annotations, it could additionally mention authentication requirements or rate limit impacts, but the core behavior is well covered.

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?

Two clear sentences for the main description, with well-organized parameter details. No redundant information; every sentence adds value. Front-loaded with purpose and outputs.

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?

Despite no output schema, the description effectively communicates return values. It covers intent, usage context, parameters, and output format. For a tool with 3 parameters and no output schema, this is comprehensive and leaves no major gaps.

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%, and the description adds extra context: required format for account_id (act_ prefix), fallback to environment variable, and period parameter with explicit predefined ranges, format, and cost warning. This adds significant value 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 it produces a performance review with period-over-period comparison, specifying outputs like current/prior metrics, delta %, and ranked callouts. It distinguishes itself from the sibling tool meta_ads_insights_report by positioning itself as an audit starting point.

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 advises use at the start of an audit to narrow attention before pulling raw insights via meta_ads_insights_report. Also mentions read-only nature, guiding appropriate usage.

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