Create mail account with domain verification

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

Annotations provide openWorldHint: true and destructiveHint: false. The description adds significant behavioral detail: it includes TXT authentication, DNS propagation wait, retries up to verification_wait_ms, and normalization of Japanese domains to ASCII. No contradiction with 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 concise sentences with no fluff. The description is front-loaded with the core purpose and efficiently covers the automation flow and domain normalization.

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?

The description explains the internal flow well, but does not mention what the tool returns (e.g., success confirmation, account ID). Since there is no output schema, the description should provide some output expectations. Missing this information reduces completeness for agent invocation.

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%, so baseline is 3. The description adds context for verification_wait_ms (total wait limit) and poll_interval_ms (retry interval), but does not explain other parameters beyond what the schema already provides. Does not improve understanding significantly.

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 the tool's purpose: a high-level tool that automates domain verification and DNS propagation wait before creating a mail account. It uses specific verbs (内包, 自動実行) and distinguishes itself from siblings like create_mail_account and ensure_domain_verified by being the composite flow.

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 implicitly guides usage by explaining the automated steps (existing check, ensure_domain_verified, POST /mail with retries). It contrasts with simpler tools like create_mail_account, but does not explicitly state when to use this tool over alternatives.

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