Create Domain

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

Annotations indicate idempotent and non-destructive. The description adds context: 'This does not purchase a domain; it creates DNS records and verification state.' This clarifies the non-purchasing aspect and the resulting state, going beyond 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, no wasted words. The key action and critical clarification (no purchase) are front-loaded. Efficient and easy to parse.

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?

Given the output schema, annotations, and 2 parameters, the description is largely complete. It covers the core behavior and constraints. Could mention required DNS pre-configuration or response format details, but not a major gap.

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 100%, with well-described parameters. The description does not add meaning beyond what the schema already provides for 'name' and 'idempotency_key'. 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?

The description clearly states what the tool does: 'Add an existing domain to ShipMail.' It distinguishes from purchasing a domain and explains the created artifacts (DNS records, verification state). Among siblings like get/list/verify/delete, this tool's role is 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?

The description implies usage when one has an existing domain to add, but lacks explicit guidance on prerequisites (e.g., domain ownership) or when not to use it (e.g., if domain needs purchasing). No alternatives or exclusions are mentioned.

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