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

With no annotations, the description carries the full behavioral burden. It helpfully discloses that queries are live against 1.1.1.1 and lists the record types, but it does not describe failure behavior, rate limits, caching, or return/error handling.

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 two compact sentences with no filler. The core operation is front-loaded, followed by the practical use cases.

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 one-parameter DNS lookup, the description provides enough context to invoke the tool: supported record types, live resolver, and use cases. Because no output schema exists, it could say more about result shape or error behavior, but the core invocation context is 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?

There is one parameter and schema description coverage is 100%, so the schema already defines `host` with an example. The description adds only the generic phrase 'for a domain' and does not supplement the schema with format constraints such as scheme omission or IDN handling.

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 states a specific verb and resource: resolve DNS records for a domain, and it lists the exact record types supported. This makes the tool clearly distinct from the sibling network/diagnostic tools such as http_head, ssl_check, and seo_snapshot.

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?

It gives clear usage contexts: verifying that a domain resolves, checking mail routing, and inspecting TXT/SPF records. It does not name exclusions or alternatives, but the intended use cases are explicit enough for an agent to select it correctly.

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