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

With no annotations provided, the description carries the full burden of behavioral disclosure, but it discloses nothing. It does not state whether the call is read-only, what data it returns, what side effects may occur, or whether network access is required. The name hints at domain expiry, but the description itself reveals no behavior.

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 short, but this is under-specification rather than effective conciseness. 'Domain Expiry: Domain Expiry' is a redundant phrase that earns no place and leaves every decision-relevant detail unspecified.

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 has no annotations, no output schema, two ambiguous parameters, and a tautological description. There is no mention of return value, required inputs, error behavior, or usage context, so the definition is far too incomplete for an agent to select and invoke the tool correctly.

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 lists two parameters, 'input' and 'domain', with generic descriptions 'Input to process' and 'Domain to process', so the description adds no semantic value. While schema coverage is nominally 100%, the parameter descriptions are boilerplate and do not explain formats, which parameter is primary, or how they relate. An agent cannot confidently populate these parameters based on available information.

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 is exactly 'Domain Expiry: Domain Expiry', a tautology that only restates the tool name. It provides no verb, no resource, and no behavior, so an agent cannot determine whether this tool checks expiration status, returns a date, or monitors domain expiry. It also does nothing to distinguish itself from closely related siblings like x402-domain-age, x402-whois, or x402-cert-expiry.

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?

There is no guidance on when to use this tool versus the many nearby domain-related tools. The description contains zero context about the intended input, the expected use case, or which sibling should be preferred instead. An agent has no basis for choosing this tool over alternatives.

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