google_ads_negative_placements_add

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

Discloses mutating and delivery-affecting nature, warns about zero impressions, mentions action_log recording with observation window, and reversibility via rollback_apply removing exactly created criteria. This goes well beyond schema and compensates for absent 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?

Three sentences: purpose, return values, effects/alternative. No filler; each sentence carries distinct, valuable information. Front-loaded with the core action.

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?

Covers purpose, scope, return values, side effects, reversibility, and tool differentiation. Given no output schema, the description adequately explains what to expect. Could mention customer_id fallback but schema already does.

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 covers 100% of parameters with descriptions, so baseline is 3. The description adds return-value semantics (criterion_id, resource_name, etc.) but no additional parameter-specific guidance beyond what 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 opens with a specific verb ('Excludes'), names the exact resource types (websites, mobile apps, mobile app categories), and clarifies scope (campaign or ad group level). It also distinguishes from sibling google_ads_negative_keywords_add by explicitly directing search-term exclusions there.

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 states when to use the alternative tool: 'Exclude search terms with google_ads_negative_keywords_add instead.' Also implies use case: blocking placements at campaign/ad group level. Provides context for batching and scope.

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