google_ads_budget_efficiency

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

With no annotations, the description discloses key behavioral traits: read-only, per-campaign data sourced from get_performance_report, silent failure handling as zero, and verdict thresholds. It does not mention auth requirements or edge cases like zero enabled campaigns, but it goes well beyond a basic action statement.

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 front-loaded with the core action, then compacts return structure, failure handling, read-only status, and alternatives into a dense but efficient text. 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?

The return object is fully specified, including exact field names and verdict logic, along with data source, failure handling, and read-only nature. Minor gaps exist (e.g., behavior when no campaigns are enabled), but for a read-only analysis tool with no annotations or output schema, this is quite complete.

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 both parameters are thoroughly described in the schema (period default and use cases, customer_id format and fallback). The description itself adds no extra parameter-level meaning, so the baseline of 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 opens with a specific verb ('Score') and resource ('budget allocation efficiency across every ENABLED Google Ads campaign'), clearly distinguishing this from sibling tools like google_ads_budget_reallocation and google_ads_budget_update.

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?

Explicit guidance is provided: 'For a concrete DECREASE/INCREASE reallocation plan use google_ads_budget_reallocation; to change a single budget use google_ads_budget_update.' The schema also advises on period selection for different diagnostic needs, so the tool can be used correctly.

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