google_ads_ad_groups_create

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

With no annotations, the description carries the full burden. It discloses that the tool is mutating, reversible via rollback (which pauses rather than deletes), and includes constraints on parent campaign status. This provides good behavioral context beyond the input 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?

The description is extremely concise: two sentences that convey purpose, constraints, and follow-up actions. Every sentence is valuable and front-loaded. No unnecessary words.

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?

Given the tool has 4 parameters with 100% schema coverage and no output schema, the description adequately covers the action, constraints, return values, and next steps. It also addresses reversibility. All critical context is present.

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 meaningful context for 'customer_id' (fallback to credentials) and 'cpc_bid_micros' (inherit defaults when omitted), which goes beyond the schema. Other parameters are adequately covered by schema.

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 'Creates a new ad group inside an existing campaign' with a specific verb and resource. It distinguishes from sibling tools like list and update by specifying the creation action and return values.

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 provides explicit guidance: prerequisites (parent campaign must be ENABLED or PAUSED), next steps (use google_ads_ads_create and google_ads_keywords_add), and mentions reversibility via rollback_apply. This clearly tells when to use the tool and what to do after.

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