Create Domain

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

Beyond the annotations, the description discloses the verification prerequisite, expected DNS propagation time, return fields, and the 409 conflict behavior. These details materially help an agent avoid calling the tool prematurely or misinterpreting an already-existing domain.

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 front-loaded with purpose, followed by the verification workflow, return behavior, and error case. It is efficient overall, though the return-value sentence slightly duplicates what the output schema already captures.

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 prerequisite verification workflow and output schema, the description covers what an agent needs: when the domain must be verified, how to verify it, expected propagation delay, return fields, and the duplicate-domain error. No critical invocation context is missing.

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 fully documents the single 'domain' parameter with format guidance. The description reinforces that the domain is for email hosting and appears in the TXT record name, but adds no new syntax or constraints 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: 'Adds a new domain to the account for email hosting.' It distinguishes the operation from sibling tools like create_domain_pointer by tying it to email hosting and domain verification.

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?

It gives clear preconditions: verify the domain first by calling get_verification_key, adding a TXT record, and waiting for DNS propagation. It also explains the 409 error for existing domains, though it does not explicitly compare alternatives such as get_domain or list_domains.

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