Create a non-payer child account

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

The description discloses critical behavioral traits beyond annotations: credentials are handed out only once and must be stored immediately, the account is non-payer and must be funded by the parent, the operation cannot be undone (no rename/delete), and calling twice creates two accounts. This aligns with openWorldHint and idempotentHint annotations, adding depth without contradicting them.

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 concise and front-loaded: the first sentence states the core action and the critical credential warning, followed by two clarifications. Every sentence contributes value, with no redundancy.

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?

With annotations and schema covering safety and parameters, the description fills the remaining gaps: it explains the return value, non-idempotence, and account limitations. Given the tool's complexity and the lack of an output schema, the description is 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?

The schema already provides full coverage (100%) for both parameters, including descriptions for shortName and isSelfAdvertisingEnabled. The description does not add additional parameter-specific meaning, so a baseline score of 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?

The description uses a specific verb and resource: 'Creates a non-payer child account under the configured agency account' and distinguishes itself by stating 'Cannot create a payer account' and contrasting with sibling tools like create_sandbox_account and transfer_funds. It also clearly states the return value.

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 provides clear context: non-payer accounts cannot top up their own balance and should be funded via transfer_funds. It also states limitations ('Cannot create a payer account, cannot rename or delete one') which serve as when-not-to-use guidance, though it does not name alternative tools explicitly.

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