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

Annotations already declare destructiveHint=true and idempotentHint=false, so the safety profile is covered. The description adds real value beyond that: it discloses the operational consequence (email stops until another domain is selected) and that the domain is retained in the Resend account, implying removal here is not an irreversible deletion.

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?

Three short sentences, all load-bearing: action, consequence, and retention scope, with the consequence front-loaded. No filler.

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 single-param destructive mutation with annotations present and no output schema, the description supplies the key consequence and reversibility context an agent needs. Minor gaps remain (e.g., whether inbound mail to the domain is dropped or bounced, and whether re-adding restores delivery), but nothing essential 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?

One parameter at 100% schema description coverage, so the schema fully documents 'domainId'. The description adds no format, source, or lookup guidance beyond it; baseline 3 applies.

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 ('Remove an email domain from HelpWell') and adds scope detail ('It stays in the Resend account') that separates it from delete-style or disconnect_resend siblings. It does not explicitly name any sibling, but the semantics are 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?

Usage is implied by the destructive framing and the note that email stops until another domain is chosen, which hints at when removal is appropriate. However, it never states when to prefer this over update_mail_domain or disconnect_resend, nor any prerequisites or confirmations required.

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