google_ads_ads_list

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

The description explicitly states 'Read-only' and lists the returned fields (id, ad_group_id, status, type, final_urls, approval_status, creative summary), providing transparency about its behavior and output. It lacks deeper details on edge cases or pagination, but with no annotations provided, it carries the transparency burden well and does not contradict any annotations.

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 and well-structured: the first sentence states the main action and optional filters, the second details the return fields, and the third provides usage context and related tools. Every sentence adds value with no redundancy or fluff.

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?

A list tool with no output schema, but the description compensates by enumerating the returned fields and including a creative summary. It also provides usage context, relationship to sibling tools (update, policy_details), and clarifies the read-only nature. This makes it complete for an agent to select and invoke the 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?

The input schema already has 100% coverage with clear descriptions for all three parameters (ad_group_id, customer_id, status_filter). The description mentions 'scoped to one ad group and/or filtered by status', which summarizes the parameters but does not add new semantic meaning beyond what the schema provides. Baseline of 3 is appropriate given full schema coverage.

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 the tool's function: 'Lists ads in a Google Ads account' with optional scoping and filtering. It distinguishes itself from siblings by explicitly referencing ads.update/update_status for ad_id lookup and pointing to policy_details for disapproval details, making it distinct from update and policy tools.

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 usage guidance is provided: 'Use this to find an ad_id before calling ads.update / update_status or to audit creative inventory. For disapproval details, follow up with google_ads_ads_policy_details.' This clearly indicates when to use this tool and which alternatives to choose for related tasks.

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