google_ads_ad_groups_update

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

With no annotations, the description carries full burden. It discloses mutating nature, reversibility via rollback_apply, and partial update behavior. Missing details on error conditions or permission requirements, but still adds valuable context beyond schema.

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?

Three sentences, front-loaded with purpose, followed by behavioral details and non-cascade advice. Every sentence is useful and no redundant information.

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?

No output schema, but description mentions returns updated ad group. Explains partial update and non-cascade. Slightly incomplete: missing prerequisites (e.g., ad group must exist) or behavior on invalid fields, but adequate for an update tool.

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%, so baseline is 3. The description adds no new semantic information about parameters beyond what the schema already provides (e.g., fallback behavior for customer_id is already in schema description).

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 states 'Updates one or more settings on an existing ad group' with specific verb and resource, and distinguishes from sibling tools like create and list.

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 describes partial update behavior and clearly states 'Does not cascade to ads or keywords under this ad group; use google_ads_ads_update / update_status and google_ads.keywords.* for those.' Provides clear when-to-use and alternative tools.

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