Campaigns Add Campaign Targeting

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

Annotations already indicate this is mutating (readOnlyHint=false), not idempotent, and not destructive. The description's 'Adds' is consistent with those annotations and clarifies that the operation is additive, but it adds little behavioral context beyond that—no mention of duplicate behavior, validation, or what happens to existing targeting.

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 a single, front-loaded sentence that communicates the verb, the objects, and the scope without waste. Every word contributes meaning and there is no filler.

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 rich input schema (100% parameter coverage) and the presence of an output schema, the one-sentence description is largely sufficient to orient an agent. It clearly identifies the operation and scope, though it could be more complete by noting when the sibling ad-group-level or removal tools should be used instead.

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%, so the schema already documents all 8 parameters. The description's mention of 'locations, languages and campaign-level negative keywords' mirrors the parameter names and adds no new semantic detail beyond what the schema provides.

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 uses a specific verb ('Adds') with a clear resource: 'locations, languages and campaign-level negative keywords to a campaign.' This specifies both the object and the scope, and 'campaign-level' distinguishes it from sibling tools like ad_groups_add_ad_group_negative_keywords and campaigns_remove_campaign_criteria.

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 intended use is implied: use this tool when adding locations, languages, or campaign-level negative keywords to a campaign. However, it does not explicitly state when not to use it or point to alternatives such as ad_groups_add_ad_group_negative_keywords for ad-group-level negatives or campaigns_remove_campaign_criteria for removals.

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