Compare DNS products

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

Annotations already cover read-only, open-world, and idempotence. The description adds useful behavioral context beyond that: the output is a comparison matrix with slim rows, and prices depend on the session city. No contradictions with the 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?

Three short, information-dense sentences. The core action and scope are front-loaded, and the alternative-tool guidance and price behavior are each given their own concise sentence with no filler.

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 annotations already declare safety and idempotence, and the schema fully documents parameters, the description covers the essential remaining context: output shape, product count, preference over a sibling, and session-city-dependent pricing. It is sufficient for correct invocation.

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 description coverage is 100%, so the schema already fully documents 'products', 'compact', and 'rich'. The description adds little beyond restating the 2–8 product constraint, which is acceptable since the schema carries the parameter semantics.

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') and a bounded resource scope ('2–8 products'), and describes the result shape ('matrix of shared characteristics + slim product rows'). It is clearly distinguishable from sibling tools like dns_product_specs and dns_product_details.

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?

Explicitly directs the agent to prefer this tool over running parallel dns_product_specs calls. This gives clear when-to-use guidance and names the alternative, which is exactly what an agent needs for tool selection.

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