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

With no annotations provided, the description carries the behavioral disclosure burden. It usefully reveals that the tool compares A records from three named resolvers, but it does not mention input expectations, edge cases, rate limits, or how the comparison is performed.

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 and front-loaded: 'Compare A records across Google/Cloudflare/Quad9' is the core value statement with no wasted text. The leading label 'DNS Propagation' is slightly redundant with the title, so it is not perfect.

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 enough that the description covers its main purpose, and an output schema exists to explain return values. However, the lack of q parameter documentation and the absence of any when-to-use nuance leaves the definition minimally viable but incomplete.

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?

The schema has a single parameter 'q' with 0% description coverage, and the description never explicitly states that 'q' should be a domain name. The purpose does strongly imply q is the domain to check, but the absence of explicit parameter guidance leaves an inference gap for the agent.

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 ('Compare'), a specific resource ('A records'), and a specific scope ('across Google/Cloudflare/Quad9'). This clearly indicates what the tool does and sets it apart from generic DNS lookup siblings, though it does not explicitly name an alternative tool.

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?

Usage is implied: checking DNS propagation by comparing A records at different public resolvers. The description does not explicitly state when to use this tool instead of similar DNS tools, nor does it provide exclusions or alternative routing guidance.

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