Add keywords

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

Annotations already establish write, idempotent, non-destructive behavior, and the description adds valuable context about validate_only acting as a dry-run that checks policy/duplicate errors without saving. It also clarifies that cpc_bid is in currency units. No contradiction with 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?

Two sentences, front-loaded with the action, and no filler. Every clause carries meaning: the resource, the keyword fields, and the validation mode.

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?

The definition is adequate for invocation because required parameters are visible in the schema, but with no output schema and no sibling differentiation it leaves some gaps. An agent may not know what the response contains or when to choose add_negative_keywords 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 coverage is only 20%, so the description must compensate. It explains the keyword subfields (text, match_type, cpc_bid) and validate_only, but it leaves ad_group_id and status semantics to the schema, which lacks descriptions. Helpful but not complete for all parameters.

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?

Description starts with 'Add keywords to an ad group,' a specific verb+resource statement that clearly distinguishes this from sibling tools like update_keyword and add_negative_keywords. It also outlines the main object shape (text, match type, optional bid), making the tool's job unambiguous.

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?

There is no explicit when-to-use guidance or comparison with alternatives. The only usage hint is the validate_only mode, but the description never states when to prefer this tool over add_negative_keywords, update_keyword, or mutate.

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