update_keyword_bid

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

Without annotations, the description discloses the preview/confirm mechanism and the cap on changes. This is a key behavioral trait. However, it does not detail error scenarios, required permissions, or output structure, which limits full transparency.

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 concise sentence with no redundant words. It front-loads the primary action and adds crucial behavior details efficiently.

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?

Despite having an output schema, the description does not mention return values or error handling. With 5 parameters, no annotations, and no parameter descriptions in schema, the description leaves significant gaps for an agent to use correctly. The preview behavior is helpful but not enough.

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 0%. The description adds meaning only for 'cpc_bid_micros' (units in micros) and 'confirm' (preview vs apply). The other three required parameters ('customer_id', 'ad_group_id', 'criterion_id') are left unexplained, which is insufficient.

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 the verb 'Set' and the resource 'keyword's max CPC bid' with units in micros. It distinguishes from sibling tools like 'update_ad_group_bid' which targets ad group bids. The preview behavior adds specificity.

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 explains that the tool previews changes by default and only applies when 'confirm=true', and that changes are capped. This provides clear context on how to use it for testing vs execution, though it does not explicitly contrast with sibling tools.

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