google_ads_ad_groups_update

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

Discloses key behaviors: partial update, mutating, reversible, non-cascading. Without annotations, the description carries full burden and does so well, though it could mention authorization requirements or error scenarios.

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 concise sentences, front-loaded with main action, then key details on partial update and return, finally alternatives and limitations. No wasted 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?

Covers essential aspects: partial update, mutability, reversibility, return value, non-cascade, and alternatives. Lacks only minor details like error states or rate limits, but within acceptable bounds given no output schema.

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?

Input schema already has 100% coverage with clear descriptions. The description adds minor context ('Partial update — only provided fields are changed') but does not significantly enhance meaning beyond schema. Baseline 3 is appropriate.

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?

Clearly states the tool updates settings on an existing ad group, with specific verb 'Updates' and resource 'ad group'. Distinguishes from sibling tools like ads update and keywords update by explicitly mentioning they are elsewhere.

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?

Provides explicit when-to-use (update ad group settings) and when-not-to-use (does not cascade to ads/keywords, directs to specific sibling tools). Also mentions reversibility via rollback_apply, giving complete usage context.

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