list_dns_subdomains

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds nothing behavioral beyond that — no note on pagination, ordering, result size, or what an empty result means.

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?

A single tightly-scoped sentence that is front-loaded with the action and resource, and the parenthetical method reference is compact. Nothing is padded, though it is arguably under-specified rather than truly concise.

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 read-only single-parameter list tool with full schema coverage the description is minimally adequate, but with no output schema it still omits return shape and pagination expectations that an agent would need to consume results 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 100% and there is only one parameter (server_id), so the schema carries the burden. The description's 'by server ID' adds no meaning beyond the schema's own 'Server ID' entry, making the baseline 3 correct.

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 (List) and resource (subdomains) scoped by server ID, plus the underlying API method. It is distinguishable in principle from siblings like list_dns_domains, but it never names those siblings or clarifies the subdomain-vs-domain boundary.

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 guidance on when to choose this tool over list_dns_domains, get_dns_zone, or the add/edit/delete subdomain siblings. Usage is only implied by the noun 'subdomains'.

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