mail_setup_mailru

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

Annotations declare destructiveHint=true, readOnlyHint=false, and openWorldHint=false. The description adds substantial value beyond annotations: it specifies exactly which records are set (MX and TXT SPF with exact values), what is preserved (other TXT records are kept), what is not touched (A records, NS, other TXT), and the special requirement that CAA/SRV records necessitate force=True. This goes well beyond the binary annotation flags, though it doesn't discuss permissions or rate limits.

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?

The description is a single, well-structured block that front-loads the core action (setting MX and SPF) followed by details on values, preservation, and side effects. It is reasonably sized for a DNS mutation tool, though the DKIM note is somewhat tangential since it describes a manual step not performed by this 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?

Given that an output schema exists, the description need not explain return values. It adequately covers what the tool does, which records are modified, what is preserved, and the force parameter's purpose. It lacks explicit usage guidelines and full parameter semantics, but for a destructive DNS operation with clear annotations, it provides enough context to invoke correctly.

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%, meaning the parameters fqdn and force have no formal descriptions. The description does mention fqdn (domain name) and force (continue when CAA/SRV exist), which adds meaning beyond the bare schema titles. However, the description only partially compensates for the zero coverage — it doesn't explain the fqdn format or edge cases for force. The provided info is useful but insufficient for full parameter understanding.

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 names a specific resource and verb: it sets MX and SPF records for Mail.ru for business in one call. It clearly contrasts with siblings like dns_set_mx or dns_set_txt by being a bundled setup, and the sibling mail_setup_yandex suggests a parallel purpose, but the description does not explicitly differentiate itself from all other DNS/mail setup tools. The inclusion of exact MX and SPF values makes the tool's unique bundling clear.

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 context is implied (for setting up Mail.ru business email), but there is no explicit when-to-use or when-not-to-use guidance. The tool doesn't state prerequisites like domain ownership verification or that it should be used instead of individual dns_set_mx and dns_set_txt calls. It also doesn't mention alternatives such as mail_set_domain_mail or mail_setup_yandex.

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