Google Ads Data Inventory

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

Annotations already indicate read-only and idempotent behavior. The description adds valuable non-obvious context: the tool does not call Google Ads APIs and does not expose user data. This goes beyond what annotations provide, clarifying its safety and scope.

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 sentences, front-loaded with the primary action. No extraneous information. Every sentence serves a purpose: stating functionality and noting limitations.

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 tool is simple with one optional parameter and an output schema exists. The description covers the tool's purpose, what it lists, and what it does not do. No additional context is needed for an AI agent to use this tool correctly.

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 has one parameter (response_format) with 0% description coverage. The tool description does not explain the parameter's purpose or default behavior, leaving the agent to infer from the enum values. With no schema descriptions, the description should compensate but fails to do so.

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 lists supported Google Ads data domains, scopes, privacy boundary, and recommended first calls. It also explicitly says what it does not do (call APIs or expose user data), distinguishing it from sibling tools that perform data fetching or mutations.

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 implies it is a starting point ('recommended first calls') but does not explicitly state when to use this tool versus alternatives like list_accounts or cache_status. No exclusion criteria or alternative tools are mentioned.

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