Register Domain

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

Without annotations, the description must disclose behavioral traits, but it only states 'send command'—failing to clarify whether this is a synchronous or asynchronous operation, whether it charges the client, or what happens on failure. The mutation intent is implied but not confirmed, and no side effects are described.

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 extremely concise (6 words), but it lacks essential detail. While brevity is positive, the content is too sparse to be helpful, falling into under-specification rather than efficient clarity.

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 tool registers a domain (a significant action with financial implications), the description omits critical context: return values, error scenarios, and how it relates to client billing or domain availability. The completeness is insufficient for a tool requiring careful 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?

Input schema has 100% description coverage for both parameters ('domainid' and 'domain'), so the description adds no extra meaning. Baseline is appropriate given the schema already documents the parameters.

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 'Send domain registration command to registrar' indicates the tool deals with domain registration but uses vague phrasing ('send command') rather than explicitly stating it registers a domain. The tool name clarifies the purpose, but the description does not effectively distinguish it from siblings like 'whmcs_renew_domain' or 'whmcs_transfer_domain'.

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?

No guidance is provided on when to use this tool versus alternatives, nor are there any prerequisites or conditions (e.g., domain availability, required permissions) mentioned. The description is purely operational without contextual usage cues.

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