Open Search MCP

Instructions

Implementation Reference

• src/tools/testing/jsonplaceholder-tools.ts:89-122 (handler)

  The execute handler function for the 'test_jsonplaceholder' tool. It simulates JSONPlaceholder API calls using mock data based on the provided endpoint ('posts', 'users', 'comments') and optional id, returning structured success/error responses.

  execute: async (args: ToolInput): Promise<ToolOutput> => {
    try {
      const { endpoint = 'posts', id } = args;
      const baseUrl = 'https://jsonplaceholder.typicode.com';
      const url = id ? `${baseUrl}/${endpoint}/${id}` : `${baseUrl}/${endpoint}`;
  
      // Simulate API response
      const mockData = {
        posts: [{ id: 1, title: 'Test Post', body: 'Test content', userId: 1 }],
        users: [{ id: 1, name: 'Test User', email: 'test@example.com' }],
        comments: [{ id: 1, postId: 1, name: 'Test Comment', email: 'test@example.com', body: 'Test comment body' }]
      };
  
      return {
        success: true,
        data: {
          endpoint,
          url,
          response: mockData[endpoint as keyof typeof mockData] || [],
          status: 'success'
        },
        metadata: {
          tool: 'test_jsonplaceholder',
          timestamp: new Date().toISOString()
        }
      };
    } catch (error) {
      return {
        success: false,
        error: `JSONPlaceholder test failed: ${error instanceof Error ? error.message : String(error)}`,
        data: null
      };
    }
  }

• src/tools/testing/jsonplaceholder-tools.ts:73-88 (schema)

  Input schema definition for the 'test_jsonplaceholder' tool, specifying optional 'endpoint' (enum of JSONPlaceholder endpoints) and 'id' parameters.

  inputSchema: {
    type: 'object',
    properties: {
      endpoint: {
        type: 'string',
        enum: ['posts', 'users', 'comments', 'albums', 'photos', 'todos'],
        description: 'JSONPlaceholder endpoint to test',
        default: 'posts'
      },
      id: {
        type: 'number',
        description: 'Specific resource ID to fetch (optional)'
      }
    },
    required: []
  },

• src/tools/testing/jsonplaceholder-tools.ts:68-123 (registration)

  Tool registration block within registerJSONPlaceholderTools function, defining name, description, schema, and handler for 'test_jsonplaceholder'.

  registry.registerTool({
    name: 'test_jsonplaceholder',
    description: 'Test JSONPlaceholder API for JSON data validation',
    category: 'testing',
    source: 'JSONPlaceholder',
    inputSchema: {
      type: 'object',
      properties: {
        endpoint: {
          type: 'string',
          enum: ['posts', 'users', 'comments', 'albums', 'photos', 'todos'],
          description: 'JSONPlaceholder endpoint to test',
          default: 'posts'
        },
        id: {
          type: 'number',
          description: 'Specific resource ID to fetch (optional)'
        }
      },
      required: []
    },
    execute: async (args: ToolInput): Promise<ToolOutput> => {
      try {
        const { endpoint = 'posts', id } = args;
        const baseUrl = 'https://jsonplaceholder.typicode.com';
        const url = id ? `${baseUrl}/${endpoint}/${id}` : `${baseUrl}/${endpoint}`;
  
        // Simulate API response
        const mockData = {
          posts: [{ id: 1, title: 'Test Post', body: 'Test content', userId: 1 }],
          users: [{ id: 1, name: 'Test User', email: 'test@example.com' }],
          comments: [{ id: 1, postId: 1, name: 'Test Comment', email: 'test@example.com', body: 'Test comment body' }]
        };
  
        return {
          success: true,
          data: {
            endpoint,
            url,
            response: mockData[endpoint as keyof typeof mockData] || [],
            status: 'success'
          },
          metadata: {
            tool: 'test_jsonplaceholder',
            timestamp: new Date().toISOString()
          }
        };
      } catch (error) {
        return {
          success: false,
          error: `JSONPlaceholder test failed: ${error instanceof Error ? error.message : String(error)}`,
          data: null
        };
      }
    }
  });

• src/index.ts:245-245 (registration)

  Main server registration call in OpenSearchMCPServer.registerAllTools() that invokes the registration of 'test_jsonplaceholder' (and test_httpbin).

  registerJSONPlaceholderTools(this.toolRegistry);    // 2 tools: test_jsonplaceholder, test_httpbin