refactor-mcp provides 2 tools with well-defined schemas and reasonable descriptions, but lacks critical safety patterns for destructive operations. Both tools have complete input schemas with type definitions and parameter descriptions. Tool descriptions exist but are brief (56-62 chars). The server is missing error recovery guidance, confirmation patterns for the destructive write tool, and detailed output schema documentation. Parameter descriptions are adequate but could be more prescriptive about constraints. The code_refactor tool performs unguarded file modifications without dry-run confirmation, which is a production concern.

• Expose dryRun as a required or default-true parameter on code_refactor. Require explicit confirmation (dry_run=false) before applying changes, forcing agents to preview modifications first.
• Expand tool descriptions to 100+ characters. Include WHEN to use the tool (e.g., 'Use when you need to find and replace code patterns across files'), prerequisites ('Requires valid regex syntax'), and output summary ('Returns file paths, line numbers, and matched/replaced text').
• Document output schemas in tool descriptions or add a separate field. Specify that results include: filePath, replacements (count), matches (array of {line, content, original, replaced, captureGroups}), and modified (boolean).
• Add error handling guidance to descriptions. E.g., 'If regex fails to compile, returns an error with the regex syntax issue. If file access is denied, skips that file and returns a summary of skipped files.'
• Add regex constraint hints to parameter descriptions. E.g., 'searchPattern (string): Valid JavaScript regex pattern. Must be valid RegExp syntax. Use \\d for digits, \\w for word chars, etc.'
• Implement error response categorization. Return structured errors with type (regex_error, file_access_error, no_matches) and actionable guidance ('No matches found. Try a broader pattern or verify file_pattern includes your target files.').