Create sub-account

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

Annotations already cover the safety profile (readOnlyHint=false, destructiveHint=true, non-idempotent), and the description adds genuinely non-obvious behavior: credentials are NOT returned and must be copied from the console, calls are blocked until the sub-account completes its own KYC, and the operation requires an environment flag plus confirm. That is material context an agent cannot get from structured fields.

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?

Four sentences, front-loaded with the creation action, then requirements, then the credentials caveat, then the gating condition. Dense but efficient; each sentence carries a distinct fact. Minor cost is that parentheticals and the trailing gating clause make it slightly hard to scan.

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 10-parameter, non-idempotent provisioning tool with no output schema, the description covers prerequisites (KYC, env flag, confirm), the required-parameter minimum, and the surprising absence of returned credentials. Only secondary semantics like permission inheritance on omission are left to the 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?

Schema coverage is 80%, so the schema already documents name, email, confirm, enabled, kyc_mode, rate_limit, and permissions. The description mostly restates the required-parameter rule ('only name is required', email for customer_use, confirm gating) rather than adding format, defaults, or interactions beyond the 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?

States a specific verb and resource ('Create a Vobiz sub-account under this main account') and immediately scopes it with the resource hierarchy. It also names the adjacent KYC-session sibling, letting an agent separate it from create_sub_account_kyc_session and from update_sub_account/delete_sub_account without opening other schemas.

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?

Gives clear conditions: name alone suffices, email is needed when kyc_mode is customer_use, and provisioning is gated by VOBIZ_ENABLE_PROVISIONING plus confirm: true. It points to create_sub_account_kyc_session for the follow-on KYC step, but never explicitly frames when to prefer this over update_sub_account or when not to create at all.

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