dns_lookup

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

No annotations are provided, so the description carries full burden. It explains the return type (DNS records with TTL and response time) but lacks information on side effects, permissions, rate limits, or error conditions. The tool is read-only, but this is not explicitly 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?

The description is concise: a purpose paragraph followed by an Args section and a Returns line. It is front-loaded with the main action and wastes no 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?

The tool is simple and no output schema exists, but the description only briefly mentions the return structure. It does not specify the format or fields of the returned records. For a complete picture, more detail on output would be beneficial.

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?

With 0% schema coverage, the description adds significant value by explaining each parameter: query (hostname or IP), record_type (list of types, missing ANY), and nameserver (optional example). Examples and default are helpful.

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 the tool performs DNS lookups and reverse lookups, listing specific use cases like resolving hostnames to IPs and finding MX records. This distinguishes it from sibling tools like batch_dns_lookup or asn_lookup.

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 provides explicit use cases (resolve, find MX, reverse lookup) but does not mention when not to use it or provide direct comparisons to sibling alternatives like batch_dns_lookup for multiple queries.

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