create_api_key

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

With no annotations provided, the description carries the behavioral disclosure burden. It does well by stating the auth prerequisite, the fact that the key is returned, and especially that it will not be shown again — an important security-sensitive behavior. It does not mention other behaviors like idempotency or side effects beyond creation.

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 concise sentences with no filler. The action and scope are front-loaded, followed by the auth requirement and the one-time-secret warning — each sentence carries meaningful, non-redundant information.

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?

For a simple two-parameter creation tool with no output schema, the description covers the essential operational context: what it creates, the auth condition, and the return behavior/security caveat. Only a brief note on alternatives or usage boundaries is missing, which keeps it from being fully complete.

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 both name and ad_account_id are already documented in the schema. The description adds no new parameter-level detail beyond reinforcing that the key is scoped to the ad account, matching the schema's ad_account_id semantics.

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?

States a specific verb and resource: 'Create an API key scoped to the selected ad account.' This clearly distinguishes the tool from similar siblings like create_conversion_api_key by emphasizing the API key type and ad-account scoping.

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 gives useful context about when this tool applies: creating an ad-account-scoped API key, and it names the required authorization. However, it does not explicitly say when to prefer this tool over alternatives such as create_conversion_api_key, leaving the choice somewhat to inference.

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