quran-mcp-server

Instructions

Implementation Reference

• src/handlers/resources.ts:284-319 (handler)

  The main handler function for the 'languages' MCP tool. Validates input using languagesSchema, calls languagesService.listLanguages(), logs response/error, and formats output as MCP content.

  /**
   * Handler for the languages tool
   */
  export async function handleLanguages(args: any) {
    try {
      // Validate arguments
      const validatedArgs = languagesSchema.parse(args);
      
      // Call the service
      const result = await languagesService.listLanguages(validatedArgs);
      
      // Log the response in verbose mode
      verboseLog('response', {
        tool: 'languages',
        result
      });
      
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify(result, null, 2)
          }
        ]
      };
    } catch (error) {
      verboseLog('error', {
        tool: 'languages',
        error: error instanceof Error ? error.message : String(error)
      });
      
      // Use the standardized error response utility
      const { createErrorResponse } = require('../utils/error-handler');
      return createErrorResponse(error, 'languages');
    }
  }

• src/schemas/languages.ts:10-17 (schema)

  Zod schema for validating input arguments to the 'languages' tool (optional 'language' parameter).

  export const languagesSchema = z.object({
    language: z.string().optional().describe("Language"),
  });
  
  // Export all language-related schemas
  export default {
    languages: languagesSchema,
  };

• src/server.ts:232-236 (registration)

  Registration of the 'languages' tool in the MCP server's tools list, specifying name, description, input schema, and examples.

    name: ApiTools.languages,
    description: "Get all languages",
    inputSchema: zodToJsonSchema(languagesSchemas.languages),
    examples: toolExamples['languages'],
  },

• src/server.ts:309-310 (registration)

  Dispatch/registration in the tool call switch statement: calls handleLanguages for ApiTools.languages.

  case ApiTools.languages:
    return await handleLanguages(request.params.arguments);

• src/services/languages-service.ts:30-119 (helper)

  Core service logic for listing languages: checks cache, makes API request to Quran.com /resources/languages, falls back to mock data on error.

  async listLanguages(params: z.infer<typeof languagesSchema>): Promise<LanguagesResponse> {
    try {
      // Validate parameters
      const validatedParams = languagesSchema.parse(params);
      
      // Check cache first
      const now = Date.now();
      if (this.languagesCache && (now - this.cacheTimestamp < CACHE_DURATION_MS)) {
        verboseLog('response', {
          method: 'listLanguages',
          source: 'cache',
          age: `${(now - this.cacheTimestamp) / 1000} seconds`
        });
        
        return {
          success: true,
          message: "languages executed successfully (from cache)",
          data: this.languagesCache
        };
      }
      
      try {
        // Make request to Quran.com API
        const url = `${API_BASE_URL}/resources/languages`;
        const response = await makeApiRequest(url, {
          language: validatedParams.language
        });
        
        verboseLog('response', {
          method: 'listLanguages',
          source: 'api',
          dataSize: JSON.stringify(response).length
        });
        
        // Update cache
        this.languagesCache = response;
        this.cacheTimestamp = now;
        
        return {
          success: true,
          message: "languages executed successfully",
          data: response
        };
      } catch (axiosError) {
        verboseLog('error', {
          method: 'listLanguages',
          error: axiosError instanceof Error ? axiosError.message : String(axiosError)
        });
        
        // If the API call fails, return mock data
        verboseLog('response', {
          method: 'listLanguages',
          source: 'mock',
          reason: 'API unavailable'
        });
        
        const mockData = this.getLanguagesMockData();
        
        return {
          success: true,
          message: "languages executed with mock data (API unavailable)",
          data: mockData
        };
      }
    } catch (error) {
      verboseLog('error', {
        method: 'listLanguages',
        error: error instanceof Error ? error.message : String(error)
      });
      
      if (error instanceof z.ZodError) {
        throw new ApiError(`Validation error: ${error.errors.map(e => `${e.path.join('.')}: ${e.message}`).join(', ')}`, 400);
      }
      
      // Return mock data as a fallback for any error
      verboseLog('response', {
        method: 'listLanguages',
        source: 'mock',
        reason: 'error occurred'
      });
      
      const mockData = this.getLanguagesMockData();
      
      return {
        success: true,
        message: "languages executed with mock data (error occurred)",
        data: mockData
      };
    }
  }