network_dns

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

With no annotations, the description must disclose behavior. It does: cost ($0.002 per call), resolver, return format (name, type code, TTL, data), NXDOMAIN behavior (unpaid 404), and caching (5 minutes). Missing details like rate limits or authentication, but the provided information is comprehensive for selection.

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 packed with useful information and is front-loaded with cost and core action. Each sentence adds value, though the first two sentences overlap slightly. Still efficient and well-structured.

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 the lack of output schema and annotations, the description adequately covers return format, caching, cost, and error behavior. It explains what the tool does and its response. Minor missing details like exact JSON structure or timeouts, but sufficient for a simple DNS lookup tool.

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 100%, so baseline is 3. The description adds no extra meaning beyond the schema: 'name' example and 'type' enumeration are already in schema. No additional syntax or format details are provided.

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 DNS records via DNS-over-HTTPS with DNSSEC validation. It lists supported record types (A, AAAA, etc.) and specifies the resolver (Cloudflare 1.1.1.1). The name 'network_dns' is self-explanatory and distinct from siblings like domains_whois (whois) and report_domain (DNS report). This is a specific verb+resource combination.

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 explicitly lists use cases: infrastructure checks, email deliverability, domain verification, and security tooling. It mentions caching and cost, providing context for when to use. While it does not explicitly state when not to use or name alternatives, the sibling tools are clearly different, so no confusion arises.

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