google_ads_monitoring_cpa_goal

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

With no annotations, the description carries the full burden and discloses critical behavior: hardcoded LAST_7_DAYS, read-only nature (does not change bids), status threshold logic, and edge cases (current_cpa None when conversions==0). It even reveals the integration of a full google_ads_cost_increase_investigate payload, which is far beyond typical descriptions.

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 compact but information-dense: a one-sentence purpose, a structured return-type list, and three brief clarifying statements (window, read-only, alternatives). Every sentence adds value, with no filler or repetition.

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 lacking an output schema, the description fully specifies the return shape, status thresholds, the cost_analysis payload source, and optional suggested_workflow. It also explains the hardcoded window and alternate tools, making the tool fully understandable in context.

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 100% and each parameter has detailed descriptions (e.g., target_cpa thresholds, campaign_id format, customer_id fallback). The description itself adds no new parameter semantics beyond mentioning 'user-supplied target', so a baseline 3 is appropriate.

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 begins with a specific action: 'Evaluate a Google Ads campaign's last-7-days CPA against a user-supplied target and integrate cost-increase analysis.' It clearly identifies the resource, the metric, and the time window. It also distinguishes itself from sibling tools by naming google_ads_health_check_all and google_ads_monitoring_cv_goal for different use cases.

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 explicitly provides when-not-to-use guidance by stating 'For account-wide rollup use google_ads_health_check_all; for daily CV-count vs target use google_ads_monitoring_cv_goal.' It also notes the tool is read-only, which informs selection for side-effect-free analysis.

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