check_subdomain

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

With no annotations provided, the description bears full responsibility for behavioral disclosure. It only says 'check if available', which implies idempotency and non-destructiveness, but it does not mention authentication requirements, rate limits, or what happens on failure. The description is too minimal to convey behavioral traits beyond the tool's name.

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 a single sentence, front-loaded with the key action, and contains no unnecessary words. Every word contributes to clarity. It is maximally concise for the tool's simplicity.

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's simplicity (2 parameters, no output schema), the description omits critical context such as the return value (e.g., boolean or availability status) and error conditions. The absence of output schema increases the need for description to explain what the tool yields, which is not addressed.

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 input schema already provides 100% coverage with descriptions for both parameters (name and domain_id). The tool description adds no additional semantic context beyond the schema. Baseline 3 is appropriate as the description does not improve or detract from parameter understanding.

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 clearly states the verb 'check' and the resource 'subdomain availability'. It effectively distinguishes itself from siblings like 'list_subdomains' (which lists existing) and 'register_subdomain' (which registers), making its unique purpose unambiguous.

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?

The description provides no guidance on when to use this tool versus alternatives. For example, it doesn't mention that it should be used before registering a subdomain, or that it only checks availability and not other properties. Sibling names imply context, but the description itself lacks explicit usage instructions.

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