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Check domain availability across 600+ TLDs without leaving Claude
Single tool with adequate schema and description, but description contains problematic instruction text (CRITICAL OUTPUT RULE) that should not be in tool descriptions. Schema is complete with proper types. However, the description is 600+ characters and includes meta-instructions about output formatting that belong in system prompts, not tool definitions. Parameter descriptions are minimal. No output schema documented. Error handling is basic.
Check domain availability on Namecheap. Returns results with pricing and purchase links. Use this tool to help users find domains that match their project, budget, and brand. Supports 600+ TLDs (.com, .net, .org, .io, .ai, etc). Consider suggesting creative alternatives across different price points and TLD options. CRITICAL OUTPUT RULE: You MUST copy the tool output VERBATIM into your response as a markdown code block. DO NOT extract URLs only. DO NOT reformat. DO NOT summarize. The output already contains domain names, prices, and formatted links - show it exactly as returned. Users need to see domain names, not just URLs.
Tool description contains meta-instructions ('CRITICAL OUTPUT RULE: You MUST copy...') that should be in system prompts, not tool definitions. This violates pattern:tool-description which requires descriptions to explain WHAT the tool does, not HOW the LLM should format responses.
No output schema documented. The tool returns structured markdown with sections (Available Domains, Premium Domains, Already Registered) but LLMs cannot infer this structure. Document the response format so agents can parse results reliably.
Parameter 'domains' lacks format guidance. Description says 'e.g., ["example.com", "test.io"]' but does not specify: are TLDs required? Are subdomains allowed? What is the max array length? LLMs need explicit constraints.
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-23 | F | 49 | 2026-07-28+ | v2 |
Error handling is minimal. When domains array is empty, the tool returns a generic error. No guidance on retryability, no suggestions for recovery, no categorization of error types (user-fixable vs fatal).
STDIO transport only. Server is not remotely accessible and cannot be used by hosted MCP clients. This is a hard architectural limitation, not a code quality issue, but it severely restricts deployment options.