diff --git a/.github/workflows/codeql-analysis.yml b/.github/workflows/codeql-analysis.yml
index ef4bb17..a829608 100644
--- a/.github/workflows/codeql-analysis.yml
+++ b/.github/workflows/codeql-analysis.yml
@@ -38,7 +38,7 @@ jobs:
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v2
+      uses: github/codeql-action/init@v3
       with:
         languages: ${{ matrix.language }}
         # If you wish to specify custom queries, you can do so here or in a config file.
@@ -52,7 +52,7 @@ jobs:
     # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
     # If this step fails, then you should remove it and run the build manually (see below)
     - name: Autobuild
-      uses: github/codeql-action/autobuild@v2
+      uses: github/codeql-action/autobuild@v3
 
     # ℹ️ Command-line programs to run using the OS shell.
     # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
@@ -65,4 +65,4 @@ jobs:
     #   ./location_of_script_within_repo/buildscript.sh
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v2
+      uses: github/codeql-action/analyze@v3
diff --git a/src/core.ts b/src/core.ts
index 100691a..fe1ba41 100644
--- a/src/core.ts
+++ b/src/core.ts
@@ -12,6 +12,7 @@ import { debug as Debug } from 'debug';
 import { createServer } from 'http';
 import { promisify } from 'util';
 import { logger as log } from './logger';
+import { MESSAGES } from './messages';
 
 
 let _config: any = {};
@@ -26,25 +27,25 @@ let jsonParser = promisify(bodyParser.json({ limit: '1mb' }));
  */
 const requestHandler = (request, response) => {
 
-  log.info(`Request recived, '${request.method} : ${request.url}'`);
+  log.info(MESSAGES.REQUEST_RECEIVED);
   debug('_config', _config);
   // Explicitly remove or override the X-Powered-By header
   response.setHeader('X-Powered-By', ''); 
   return Promise.resolve().then(() => {
     // Should be a POST call.
     if (request.method && request.method !== 'POST') {
-      debug('Only POST call is supported.');
+      debug(MESSAGES.ONLY_POST_SUPPORTED);
       return Promise.reject({
-        body: `Only POST call is supported.`,
+        body: `Only POST requests are supported.`,
         statusCode: 400,
         statusMessage: 'Not allowed',
       });
     }
   }).then(() => {
     // validate endpoint
-    debug(`${request.url} invoked`);
+    debug(MESSAGES.REQUEST_INVOKED(request.url));
     if (_config && _config.listener && request.url !== _config.listener.endpoint) {
-      debug('url authentication failed');
+      debug(MESSAGES.URL_AUTH_FAILED);
       return Promise.reject({
         body: `${request.url} not found.`,
         statusCode: 404,
@@ -53,12 +54,12 @@ const requestHandler = (request, response) => {
     }
   }).then(() => {
     // verify authorization
-      debug('validating basic auth', _config.listener);
+      debug(MESSAGES.VALIDATING_BASIC_AUTH, _config.listener);
       if (_config && _config.listener && _config.listener.basic_auth) {
-        debug('validating basic auth');
+        debug(MESSAGES.VALIDATING_BASIC_AUTH);
         const creds = BasicAuth(request);
         if (!creds || (creds.name !== _config.listener.basic_auth.user || creds.pass !== _config.listener.basic_auth.pass)) {
-        debug('basic auth failed');
+        debug(MESSAGES.BASIC_AUTH_FAILED);
         debug(
           'expected %O but received %O',
           _config.listener.basic_auth,
@@ -73,12 +74,12 @@ const requestHandler = (request, response) => {
     }
   }).then(() => {
     // validate custom headers
-    debug('validate custom headers');
+    debug(MESSAGES.VALIDATING_CUSTOM_HEADERS);
     if (_config && _config.listener) {
       for (const headerKey in _config.listener.headers) {
-        debug('validating headers');
+        debug(MESSAGES.VALIDATING_HEADERS);
         if (request.headers[headerKey] !== _config.listener.headers[headerKey]) {
-          debug(`${headerKey} was not found in req headers`);
+          debug(MESSAGES.HEADER_NOT_FOUND(headerKey));
           return Promise.reject({
               body: 'Header key mismatch.',
               statusCode: 417,
@@ -88,7 +89,7 @@ const requestHandler = (request, response) => {
       } 
     }
   }).then(async () => {
-    debug('parsing json');
+    debug(MESSAGES.PARSING_JSON);
     try {
       if (_config.reqBodyLimit) {
         jsonParser = promisify(bodyParser.json({ limit: _config.reqBodyLimit }));
@@ -103,13 +104,13 @@ const requestHandler = (request, response) => {
         locale = body.data.locale;
       }
       debug('_config.listener.actions[type]', _config.listener.actions[type]);
-      debug('event', event);
+      debug(MESSAGES.EVENT, event);
       // validate event:type
       if (
         !_config.listener.actions[type] ||
         _config.listener.actions[type].indexOf(event) === -1
       ) {
-        debug(`${event}:${type} not defined for processing`);
+        debug(MESSAGES.EVENT_NOT_DEFINED(event, type));
         return Promise.reject({
           body: `${event}:${type} not defined for processing`,
           statusCode: 403,
@@ -137,9 +138,9 @@ const requestHandler = (request, response) => {
       }
       data.event = event;
       _notify(data).then((data) => {
-        debug('Data [_notify]', data);
+        debug(MESSAGES.DATA_RECEIVED_NOTIFY, data);
       }).catch((error) => {
-        debug('Error [_notify]', error);
+        debug(MESSAGES.ERROR_OCCURRED_NOTIFY, error);
       });
       return Promise.resolve({ statusCode: 200, statusMessage: 'OK', body: data });
     } catch (err) {
@@ -150,7 +151,7 @@ const requestHandler = (request, response) => {
       });
     }
   }).then((value) => {
-    debug('Value', value);
+    debug(MESSAGES.VALUE, value);
     response.setHeader('Content-Type', 'application/json');
     response.statusCode = value.statusCode;
     response.statusMessage = value.statusMessage;
@@ -162,7 +163,7 @@ const requestHandler = (request, response) => {
     response.end(JSON.stringify(safeBody));
     return;
   }).catch((error) => {
-    debug('Error', error);
+    debug(MESSAGES.ERROR, error);
     const safeError = {
       statusCode: error.statusCode || 500,
       statusMessage: error.statusMessage || 'Internal Server Error',
diff --git a/src/index.ts b/src/index.ts
index e9e608f..95115c1 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -11,6 +11,7 @@ import { merge } from 'lodash';
 import { createListener } from './core';
 import { defaultConfig } from './defaults';
 import { logger as log, setLogger } from './logger';
+import { MESSAGES } from './messages';
 
 const debug = Debug('webhook:listener');
 let notify;
@@ -26,7 +27,7 @@ export function register(consumer: any) {
   if (typeof consumer !== 'function') {
     throw new Error('Provide function to notify consumer.');
   }
-  debug('register called with %O', notify);
+  debug(MESSAGES.REGISTER_CALLED, notify);
   notify = consumer;
   return true;
 }
@@ -44,7 +45,7 @@ export function start(userConfig: any, customLogger?: any) {
       if (customLogger) {
         setLogger(customLogger);
       }
-      debug('start called with %O', userConfig);
+      debug(MESSAGES.START_CALLED, userConfig);
       appConfig = merge(appConfig, userConfig)
       validateConfig(appConfig);
 
@@ -59,10 +60,10 @@ export function start(userConfig: any, customLogger?: any) {
         );
       }
 
-      debug('starting with config: ' + JSON.stringify(appConfig));
+      debug(MESSAGES.STARTING_WITH_CONFIG(JSON.stringify(appConfig)));
       const port = process.env.PORT || appConfig.listener.port;
       const server = createListener(appConfig, notify).listen(port, () => {
-        log.info(`Server running at port ${port}`);
+        log.info(MESSAGES.SERVER_RUNNING(port));
       });
       return resolve(server);
     } catch (error) {
@@ -102,14 +103,14 @@ function validateConfig(customConfig) {
           customConfig.listener.endpoint = '/' + customConfig.listener.endpoint;
         }
       } else {
-        throw new TypeError('Please provide valide listener.endpoint');
+        throw new TypeError(MESSAGES.INVALID_LISTENER_ENDPOINT);
       }
     }
     if (
       customConfig.listener.port &&
       typeof customConfig.listener.port !== 'number'
     ) {
-      throw new TypeError('Please provide valide listener.port');
+      throw new TypeError(MESSAGES.INVALID_LISTENER_PORT);
     }
   }
 }
diff --git a/src/logger.ts b/src/logger.ts
index cf58b22..6a09333 100644
--- a/src/logger.ts
+++ b/src/logger.ts
@@ -1,4 +1,5 @@
 import { Console } from 'console';
+import { MESSAGES } from './messages';
 
 let logger;
 logger = new Console(process.stdout, process.stderr);
@@ -11,10 +12,10 @@ logger = new Console(process.stdout, process.stderr);
 function setLogger(customLogger) {
     const validator = validateLogger(customLogger);
     if (!validator) {
-        console.warn('Failed to register logger, using console for logging.');
+        console.warn(MESSAGES.LOGGER_REGISTRATION_FAILED);
     } else {
         logger = customLogger;
-        logger.info('Logger registered successfully.');
+        logger.info(MESSAGES.LOGGER_REGISTERED_SUCCESS);
     }
 }
 
@@ -26,7 +27,7 @@ const validateLogger = (instance) => {
     const requiredFn = ['info', 'warn', 'log', 'error', 'debug'];
     requiredFn.forEach((name) => {
       if (typeof instance[name] !== 'function') {
-        console.warn(`Unable to register custom logger since '${name}()' does not exist on ${instance}!`);
+        console.warn(MESSAGES.UNABLE_TO_REGISTER_LOGGER(name, instance));
         flag = true;
       }
     });
diff --git a/src/messages.ts b/src/messages.ts
new file mode 100644
index 0000000..2f937e9
--- /dev/null
+++ b/src/messages.ts
@@ -0,0 +1,54 @@
+/*!
+ * contentstack-webhook-listener
+ * copyright (c) Contentstack LLC
+ * MIT Licensed
+ */
+
+'use strict';
+
+/**
+ * Centralized messages for the webhook listener.
+ * This file contains all log messages, debug messages, and error messages
+ * used throughout the application.
+ */
+
+export const MESSAGES = {
+  // Debug messages for index.ts
+  REGISTER_CALLED: 'Register called with object: %O',
+  START_CALLED: 'Start called with object: %O',
+  STARTING_WITH_CONFIG: (config: string) => `Starting with config: ${config}`,
+  
+  // Log messages for index.ts
+  SERVER_RUNNING: (port: string | number) => `Server is running on port ${port}.`,
+  
+  // Error messages for index.ts
+  INVALID_LISTENER_ENDPOINT: 'Please provide a valid listener endpoint.',
+  INVALID_LISTENER_PORT: 'Please provide a valid listener port.',
+  
+  // Log messages for core.ts
+  REQUEST_RECEIVED: 'Request received.',
+  
+  // Debug messages for core.ts
+  ONLY_POST_SUPPORTED: 'Only POST requests are supported.',
+  REQUEST_INVOKED: (url: string) => `Request invoked: ${url}`,
+  URL_AUTH_FAILED: 'URL authentication failed.',
+  VALIDATING_BASIC_AUTH: 'Validating basic authentication...',
+  BASIC_AUTH_FAILED: 'Basic authentication failed.',
+  VALIDATING_CUSTOM_HEADERS: 'Validating custom headers...',
+  VALIDATING_HEADERS: 'Validating headers...',
+  HEADER_NOT_FOUND: (headerKey: string) => `Header '${headerKey}' was not found in the request.`,
+  PARSING_JSON: 'Parsing JSON...',
+  EVENT: 'Event',
+  EVENT_NOT_DEFINED: (event: string, type: string) => `Event '${event}:${type}' not defined for processing.`,
+  DATA_RECEIVED_NOTIFY: 'Data received for [_notify].',
+  ERROR_OCCURRED_NOTIFY: 'Error occurred in [_notify].',
+  VALUE: 'Value',
+  ERROR: 'Error',
+  
+  // Logger messages
+  LOGGER_REGISTRATION_FAILED: 'Failed to register logger.',
+  LOGGER_REGISTERED_SUCCESS: 'Logger registered successfully.',
+  UNABLE_TO_REGISTER_LOGGER: (name: string, instance: any) => 
+    `Unable to register custom logger: '${name}()' does not exist on ${instance}.`,
+};
+
diff --git a/test/unit/index.test.js b/test/unit/index.test.js
index d96aec5..fa84374 100644
--- a/test/unit/index.test.js
+++ b/test/unit/index.test.js
@@ -101,7 +101,7 @@ describe("Test start method without user config.", () => {
       .then(response => {
         expect(response.statusCode).toBe(400);
         expect(response.body.error.message).toBe(
-          "Only POST call is supported.",
+          "Only POST requests are supported.",
         );
       });
   });
@@ -147,7 +147,7 @@ describe("Test start method with custom logger", () => {
   });
 });
 
-describe("Test start method with invalid user config", async () => {
+describe("Test start method with invalid user config", () => {
   test("It should throw error when endpoint in config set to number", () => {
     let config;
     register(notify);
@@ -160,7 +160,7 @@ describe("Test start method with invalid user config", async () => {
     start(config)
       .then(svr => {})
       .catch(error => {
-        expect(error.message).toBe("Please provide valide listener.endpoint");
+        expect(error.message).toBe("Please provide a valid listener endpoint.");
       });
   });
 
@@ -176,7 +176,7 @@ describe("Test start method with invalid user config", async () => {
     start(config)
       .then(svr => {})
       .catch(error => {
-        expect(error.message).toBe("Please provide valide listener.port");
+        expect(error.message).toBe("Please provide a valid listener port.");
       });
   });
 });
@@ -223,7 +223,7 @@ describe("Test start method with user config", () => {
       .then(response => {
         expect(response.statusCode).toBe(400);
         expect(response.body.error.message).toBe(
-          "Only POST call is supported.",
+          "Only POST requests are supported.",
         );
       });
   });