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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds substantial context beyond that: the DNS-over-HTTPS resolver, DNSSEC validation status, per-call cost of USD 0.002, payment via x402 with USDC on Base, and the fact that failed calls are not charged. These are meaningful operational details not captured by annotations.

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 dense sentence that front-loads the main purpose and then adds resolver, DNSSEC, and billing details. It is efficient, though the list of record types duplicates the enum values and could be trimmed.

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?

With no output schema and only 2 parameters, the description should explain the return shape more fully. It covers the resolver, DNSSEC status, and billing model, but it does not specify the response structure or what happens when the type parameter is omitted.

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 50%: the required name parameter is described as a domain name, and the type parameter is an enum without its own description. The description restates the enum values and clarifies that a domain is the target, but it does not explain the type parameter's optional/default behavior when omitted, so it only partially compensates for the schema gap.

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 that this tool retrieves DNS records for a domain, enumerates the supported record types, and identifies the resolver (DNS-over-HTTPS at 1.1.1.1). It is specific and actionable, but it does not explicitly distinguish itself from the related sibling domain_whois.

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 does not say when to use this tool versus alternatives such as domain_whois, nor does it state exclusions or prerequisites beyond the cost note. Usage is only implied by the resource name and supported record types.

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