dns_lookup

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

With no annotations present, the description carries the full disclosure burden, yet it says nothing about failure modes (NXDOMAIN, SERVFAIL), network/timeout behavior, or rate limits. The only behavioral hint is the implicit read-only nature of a lookup, which is not stated.

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 front-loaded sentence with no filler; the action and scope arrive first and the record-type list adds concrete value rather than padding.

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 two-parameter read tool with no output schema, the description covers the essentials of what is queried. It omits the default behavior when record_types is null and any indication of result shape or error conditions, which leaves gaps an agent would notice on first invocation.

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 coverage is 0%, so the description must compensate. It partially does: it enumerates the accepted record type values (A, AAAA, MX, NS, TXT, CNAME, SOA), which the schema leaves as an unconstrained string array, and ties them to the domain being resolved. It does not say what happens when record_types is omitted (schema default null) or what domain format is expected.

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?

Specific verb ('Resolve') plus resource ('DNS records') and an enumerated set of record types, so the agent knows exactly what comes back. It does not explicitly name reverse_dns as the inverse sibling, but the forward-lookup framing plus 'for a domain' makes the distinction reasonably evident.

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?

No statement of when to use this versus reverse_dns, whois_lookup, or enumerate_subdomains, and no prerequisites or exclusions. Usage is inferable from the name but not guided by the description.

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