si_check_domain

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

With no annotations, the description carries the full burden and does so reasonably: it names the upstream (ARNES whois port 43), the transport (raw socket), what is bypassed (Cloudflare queues, CAPTCHAs), and what is returned (availability plus checkout links and a Rule 10 evaluation). It omits rate limits, failure modes, and does not explicitly confirm the read-only/no-auth nature.

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?

One long sentence that is appropriately front-loaded with the core purpose, but the middle clause about 'registrar web bloat, Cloudflare queues, and CAPTCHAs' is promotional filler that displaces more useful routing or behavioral information.

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?

For a single-parameter tool with no output schema, the description gives enough to call it and hints at the return payload (availability, checkout links, rule 10 reading). However, it never resolves how it relates to the similarly named checkout and rule-10 sibling tools, leaving ambiguity about whether calling this redundantly triggers that logic.

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 coverage is 100% and the single 'domain' parameter is already documented with examples in the schema, including the 'kinging' shorthand. The description adds no syntax, format, or normalization details beyond that, so the baseline 3 applies.

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?

States a specific verb and resource: a real-time availability check for .si domains via whois (ARNES port 43). It does not differentiate from the sibling si_batch_check, so an agent must infer that this handles a single domain from the one-param schema.

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 explicit when-to-use guidance or comparison to si_batch_check, si_fast_checkout, si_evaluate_rule10, or si_api_register. The claim that it 'includes instant checkout links and GEMINI Rule 10 two-reading evaluation' actually muddies routing, since dedicated siblings appear to exist for exactly those concerns.

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