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

Annotations already declare destructiveHint=true, but the description adds crucial context beyond them: existing MX records are deleted and replaced, the SPF record is merged and rewritten, local turbopress mailboxes stop receiving mail, and DKIM requires a separate manual step. This is exactly the extra behavioral detail an agent needs for a destructive operation.

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?

Front-loaded with the action, then a clearly marked warning and follow-up steps. It is dense and somewhat long, but nearly every sentence carries operational weight given the destructive nature of the tool.

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?

Despite no output schema, the description covers side effects, prerequisites, required confirmation, and follow-up DKIM steps, and even notes that the response lists affected mailboxes. Nothing an agent needs to call it safely 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?

Schema coverage is 100%, so parameters are documented ('domain', provider enum). The description goes further by clarifying that the provider choice changes behavior (microsoft365 also sets an Autodiscover CNAME), adding meaning beyond the schema's flat enum list.

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: it switches a domain's email delivery to an external provider (Google Workspace or Microsoft 365) by setting MX/SPF/Autodiscover records. This clearly distinguishes it from siblings like create_email_account and add_dns_record.

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?

Explicitly instructs the agent to ask for confirmation before calling, to name the affected mailboxes using get_email_accounts, and to add DKIM afterward via add_dns_record. It names the alternative/prerequisite tools and the conditions selecting them.

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