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

Annotations only declare readOnlyHint=false, idempotentHint=false and destructiveHint=false; the description adds real context beyond that, disclosing that the call is an asynchronous 'queue' rather than an inline check, that the private service credential is never exposed, and that mailbox passwords and message content are not returned. It still does not say whether the result is a job handle or how to retrieve the outcome.

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?

Purpose is front-loaded and there is little padding, but the three terse permission sentences ('No guest access. Members can read. Owners, admins and organization keys can manage email.') read as pasted fragments and partially overlap, mildly diluting the core message.

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 an async queue operation with no output schema, the description should explain what the caller receives and how to follow up, but it omits any reference to polling (e.g. via commsharbor_email_job_get). The permission model and data-exposure guarantees are covered, so it is adequate but has a clear gap around the async lifecycle.

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 description coverage is 100%, so organization_id, resource_id and idempotency_key are already documented in the schema. The description adds no syntax, format, or constraint detail (e.g. what makes an idempotency_key stable or valid), so 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?

The opening clause 'Queue a check of ownership, DNS and certificates' gives a specific verb (queue) plus the concrete checks performed, which is more informative than the tautological name 'email_domain_verify'. It does not explicitly contrast itself with siblings like domain_setup or domain_get, so an agent must infer the boundary from the name alone.

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 never states when to call this tool versus domain_setup, domain_get, or domain_assistance, nor what prerequisite state (e.g. domain must exist) is required. The permission sentences describe who is authorized but not the triggering condition or ordering, leaving usage entirely implied.

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