mail_create

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

Annotations already establish readOnlyHint=false, destructiveHint=false, and openWorldHint=false, so the safety profile is carried structurally. The description adds nothing beyond that: it never says what happens if the mailbox already exists, whether quotas or provider-specific limits apply, or that the password cannot be retrieved afterward.

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?

Very short and front-loaded: the purpose is stated before the Args block, and each parameter line is one sentence. No wasted prose, though the Args section is somewhat boilerplate for parameters whose names are already self-describing.

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?

An output schema exists, so return values need not be described, and annotations cover the safety profile. What is missing is creation-specific behavior such as duplicate-mailbox handling and quota limits, which matters for a mutating mailbox-provisioning tool.

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 0%, so the description must compensate, and it partially does: it clarifies that mailbox is only the local part before "@" and gives a domain example (site.ru). However, password carries no format or strength requirements, and the domain/mailbox relationship (must the domain already exist?) is left unexplained.

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?

Concrete verb+resource ("Добавить почтовый ящик" / add a mailbox) is immediately clear and distinguishes the tool from mail_delete, mail_change_password, and mail_change_settings in the sibling set. It stops short of explicitly naming which sibling to prefer for related operations, so it lands at 4 rather than 5.

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?

There is no when-to-use guidance, no prerequisites, and no mention of alternatives even though several mail_* siblings exist. The agent must infer the entire usage context from the tool name alone.

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