list mail domains

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered. The description adds the detail that it 'Executes verified command v-list-mail-domains,' which provides a small amount of implementation context. However, it does not disclose return format details, pagination, or any other behavioral traits beyond what annotations already convey.

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 two short sentences with no wasted words. The core purpose is front-loaded in the first sentence, and the second sentence adds a small implementation detail. It is appropriately sized for a simple list operation.

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 read-only list tool with rich annotations (readOnly, idempotent, non-destructive) and an output schema, the description is mostly complete. It identifies the user scope and the operation. It could be improved by noting the 'format' parameter or explicitly distinguishing from sibling list tools, but nothing critical is missing for an agent to invoke it correctly.

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%, so the description carries the burden for parameter meaning. The description mentions 'a user's mail domains,' which maps to the required 'user' parameter, but it does not explain the 'format' parameter or its default behavior. The schema itself documents 'format' with an enum and default, so the description adds minimal value beyond the schema.

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 states a specific verb and resource: 'List a user's mail domains.' It clearly identifies the operation and the target resource. However, it does not explicitly differentiate from sibling tools like list_web_domains or list_dns_domains, though the resource name 'mail domains' makes the distinction fairly obvious.

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 implies usage context: it lists mail domains for a user, and the required 'user' parameter indicates the scope. It does not explicitly state when to use this tool versus alternatives like list_mail_accounts or get_mail_domain, nor does it mention any exclusions or prerequisites. The context is clear enough for basic selection but lacks explicit routing guidance.

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