DNS Health Check

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

Annotations already declare readOnlyHint=true, indicating a safe read operation. The description adds value by detailing the specific checks performed (IPv6, MX records, nameserver redundancy, resolution time) and the record types resolved, which goes beyond the annotation. However, it does not mention potential timeouts or error conditions.

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 sentence that efficiently conveys the full scope of the tool. It front-loads the main action ('Resolve all DNS records') and lists the checks, with no redundant words.

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 simple read-only tool with one parameter and no output schema, the description covers what the tool does but does not describe the return format or any limitations (e.g., whether it returns raw records or a summary). It is adequate but could include a note about the output to be more complete.

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?

The input schema has one parameter 'url' with a description ('Website URL or domain to check'), covering 100% of parameters. The tool description explains the overall operation but does not add specific meaning or constraints to the parameter itself, such as accepted formats or handling of relative URLs.

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 clearly states it resolves all common DNS record types (A, AAAA, MX, NS, CNAME, TXT, SOA) and checks for IPv6 support, MX records, nameserver redundancy, and resolution time. The verb 'resolve' and the list of record types make the purpose specific and distinct from sibling tools like check_ssl or check_uptime.

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 implies that the tool is for comprehensive DNS health checks, but it does not explicitly state when to use it versus alternatives or when not to use it. For example, it does not clarify if it should be used when only a specific record type is needed. The sibling tool names provide some context, but no direct guidance is given.

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