Cocos Creator MCP Server Plugin

import { ToolDefinition, ToolResponse, ToolExecutor } from '../types'; export class ValidationTools implements ToolExecutor { getTools(): ToolDefinition[] { return [ { name: 'validate_json_params', description: 'Validate and fix JSON parameters before sending to other tools', inputSchema: { type: 'object', properties: { jsonString: { type: 'string', description: 'JSON string to validate and fix' }, expectedSchema: { type: 'object', description: 'Expected parameter schema (optional)' } }, required: ['jsonString'] } }, { name: 'safe_string_value', description: 'Create a safe string value that won\'t cause JSON parsing issues', inputSchema: { type: 'object', properties: { value: { type: 'string', description: 'String value to make safe' } }, required: ['value'] } }, { name: 'format_mcp_request', description: 'Format a complete MCP request with proper JSON escaping', inputSchema: { type: 'object', properties: { toolName: { type: 'string', description: 'Tool name to call' }, arguments: { type: 'object', description: 'Tool arguments' } }, required: ['toolName', 'arguments'] } } ]; } async execute(toolName: string, args: any): Promise<ToolResponse> { switch (toolName) { case 'validate_json_params': return await this.validateJsonParams(args.jsonString, args.expectedSchema); case 'safe_string_value': return await this.createSafeStringValue(args.value); case 'format_mcp_request': return await this.formatMcpRequest(args.toolName, args.arguments); default: throw new Error(`Unknown tool: ${toolName}`); } } private async validateJsonParams(jsonString: string, expectedSchema?: any): Promise<ToolResponse> { try { // First try to parse as-is let parsed; try { parsed = JSON.parse(jsonString); } catch (error: any) { // Try to fix common issues const fixed = this.fixJsonString(jsonString); try { parsed = JSON.parse(fixed); } catch (secondError) { return { success: false, error: `Cannot fix JSON: ${error.message}`, data: { originalJson: jsonString, fixedAttempt: fixed, suggestions: this.getJsonFixSuggestions(jsonString) } }; } } // Validate against schema if provided if (expectedSchema) { const validation = this.validateAgainstSchema(parsed, expectedSchema); if (!validation.valid) { return { success: false, error: 'Schema validation failed', data: { parsedJson: parsed, validationErrors: validation.errors, suggestions: validation.suggestions } }; } } return { success: true, data: { parsedJson: parsed, fixedJson: JSON.stringify(parsed, null, 2), isValid: true } }; } catch (error: any) { return { success: false, error: error.message }; } } private async createSafeStringValue(value: string): Promise<ToolResponse> { const safeValue = this.escapJsonString(value); return { success: true, data: { originalValue: value, safeValue: safeValue, jsonReady: JSON.stringify(safeValue), usage: `Use "${safeValue}" in your JSON parameters` } }; } private async formatMcpRequest(toolName: string, toolArgs: any): Promise<ToolResponse> { try { const mcpRequest = { jsonrpc: '2.0', id: Date.now(), method: 'tools/call', params: { name: toolName, arguments: toolArgs } }; const formattedJson = JSON.stringify(mcpRequest, null, 2); const compactJson = JSON.stringify(mcpRequest); return { success: true, data: { request: mcpRequest, formattedJson: formattedJson, compactJson: compactJson, curlCommand: this.generateCurlCommand(compactJson) } }; } catch (error: any) { return { success: false, error: `Failed to format MCP request: ${error.message}` }; } } private fixJsonString(jsonStr: string): string { let fixed = jsonStr; // Fix common escape character issues fixed = fixed // Fix unescaped quotes in string values .replace(/(\{[^}]*"[^"]*":\s*")([^"]*")([^"]*")([^}]*\})/g, (match, prefix, content, suffix, end) => { const escapedContent = content.replace(/"/g, '\\"'); return prefix + escapedContent + suffix + end; }) // Fix unescaped backslashes .replace(/([^\\])\\([^"\\\/bfnrtu])/g, '$1\\\\$2') // Fix trailing commas .replace(/,(\s*[}\]])/g, '$1') // Fix control characters .replace(/\n/g, '\\n') .replace(/\r/g, '\\r') .replace(/\t/g, '\\t') // Fix single quotes to double quotes .replace(/'/g, '"'); return fixed; } private escapJsonString(str: string): string { return str .replace(/\\/g, '\\\\') // Escape backslashes first .replace(/"/g, '\\"') // Escape quotes .replace(/\n/g, '\\n') // Escape newlines .replace(/\r/g, '\\r') // Escape carriage returns .replace(/\t/g, '\\t') // Escape tabs .replace(/\f/g, '\\f') // Escape form feeds .replace(/\b/g, '\\b'); // Escape backspaces } private validateAgainstSchema(data: any, schema: any): { valid: boolean; errors: string[]; suggestions: string[] } { const errors: string[] = []; const suggestions: string[] = []; // Basic type checking if (schema.type) { const actualType = Array.isArray(data) ? 'array' : typeof data; if (actualType !== schema.type) { errors.push(`Expected type ${schema.type}, got ${actualType}`); suggestions.push(`Convert value to ${schema.type}`); } } // Required fields checking if (schema.required && Array.isArray(schema.required)) { for (const field of schema.required) { if (!Object.prototype.hasOwnProperty.call(data, field)) { errors.push(`Missing required field: ${field}`); suggestions.push(`Add required field "${field}"`); } } } return { valid: errors.length === 0, errors, suggestions }; } private getJsonFixSuggestions(jsonStr: string): string[] { const suggestions: string[] = []; if (jsonStr.includes('\\"')) { suggestions.push('Check for improperly escaped quotes'); } if (jsonStr.includes("'")) { suggestions.push('Replace single quotes with double quotes'); } if (jsonStr.includes('\n') || jsonStr.includes('\t')) { suggestions.push('Escape newlines and tabs properly'); } if (jsonStr.match(/,\s*[}\]]/)) { suggestions.push('Remove trailing commas'); } return suggestions; } private generateCurlCommand(jsonStr: string): string { const escapedJson = jsonStr.replace(/'/g, "'\"'\"'"); return `curl -X POST http://127.0.0.1:8585/mcp \\ -H "Content-Type: application/json" \\ -d '${escapedJson}'`; } }