Ad Groups Add Ad Group Negative Keywords

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

Annotations already declare readOnlyHint=false, idempotentHint=false, and destructiveHint=false, so the description need not re-state that it's a mutation. However, the description adds only the scope ('one ad group') and does not disclose whether the negatives are additive or replace an existing set, or any other behavioral nuance. With annotations providing the safety profile, the description's contribution is minimal.

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 and scope, followed by a targeted pointer to an alternative. No filler or redundant information; highly efficient.

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?

With the output schema present, return values are covered. The description plus schema cover the essential call parameters and the primary alternative. The only notable gap is clarity on whether negatives are appended or replaced, which is a behavioral detail rather than a critical invocation requirement. Overall, the description is adequate for correct usage.

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 description coverage is 100% and every parameter has a clear description, so the tool description does not need to elaborate on parameters. The baseline of 3 applies because the schema carries the semantic weight; the tool description adds no parameter-specific value beyond that.

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 a specific action ('Adds negative keywords to one ad group') with a clear resource scope (one ad group). It explicitly contrasts with campaign-wide negatives, naming the sibling tool, so an agent can easily distinguish it from campaigns.add_campaign_targeting.

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 directly says 'For campaign-wide negatives use campaigns.add_campaign_targeting,' which is an explicit when-not and alternative. It implies when to use this (ad-group-level negatives) and the scope constraint 'one ad group.' This is clear and actionable.

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