diff --git a/Dockerfile b/Dockerfile
new file mode 100644
index 0000000..836380c
--- /dev/null
+++ b/Dockerfile
@@ -0,0 +1,17 @@
+# Dockerfile for building a docker image for a type script web project. 
+# pull base image
+FROM node:12.2.0-alpine
+
+# set working directory
+WORKDIR /usr/src/app
+
+# add `/usr/src/app/node_modules/.bin` to $PATH
+ENV PATH /usr/src/app/node_modules/.bin:$PATH
+
+# install and cache dependencies
+COPY ./package.json /usr/src/app/package.json
+COPY ./main.ts /usr/src/app/main.ts
+COPY ./tsconfig.json /usr/src/app/tsconfig.json
+COPY ./yarn.lock /usr/src/app/yarn.lock
+RUN yarn
+CMD ["yarn", "start"]
\ No newline at end of file
diff --git a/README.md b/README.md
index 86b2e04..b474ecf 100644
--- a/README.md
+++ b/README.md
@@ -27,7 +27,7 @@ cp .env.example .env
 ```bash
 yarn start # or `npm start`
 ```
-4. Configure "Request URL" with `http(s)://domain:port` and add "Message received [v2.0] - im.message.receive_v1" event in "Event Subscription" - "Lark Developer App Panel".
+4. Configure "Request URL" with `http(s)://domain:port/event` and add "Message received [v2.0] - im.message.receive_v1" event in "Event Subscription" - "Lark Developer App Panel".
 5. Go to "Permissions & Scopes" and add all permissions that "im.message.receive_v1" requires and the following permissions.
 - im:message
 - im:message:send_as_bot
@@ -36,6 +36,7 @@ yarn start # or `npm start`
 
 ## Robot Command
 ```text
+/help help message
 /reset # Reset user's session context
 /img <prompt> # Generate an image with the given prompt
 ```
diff --git a/docker-compose.yml b/docker-compose.yml
new file mode 100644
index 0000000..65fb26c
--- /dev/null
+++ b/docker-compose.yml
@@ -0,0 +1,11 @@
+# docker-compose.yam file for running a web service. the image is build from the Dockerfile and the image name is larkgpt.
+version: '3'
+services:
+  larkgpt:
+    build: .
+    image: larkgpt
+    container_name: larkgpt
+    ports:
+      - "3000:3000"
+    env_file:
+      - .env
\ No newline at end of file
diff --git a/main.ts b/main.ts
index f2d6228..0c7351c 100644
--- a/main.ts
+++ b/main.ts
@@ -35,6 +35,9 @@ const INIT_COMMAND = env.INIT_COMMAND ||
   'The following is a conversation with an AI assistant. The assistant is helpful, creative, clever, and very friendly.'
 const TEXT_MODEL = env.TEXT_MODEL || 'text-davinci-003'
 const IMAGE_SIZE = env.IMAGE_SIZE || '1024x1024'
+const HELP_MESSAGE = env.HELP_MESSAGE || `/help help message
+/reset # Reset user's session context
+/img <prompt> # Generate an image with the given prompt`
 
 async function reply (
   messageID: string, content: string) {
@@ -219,6 +222,8 @@ const eventDispatcher = new lark.EventDispatcher({
         if (content === '/reset') {
           cache.del(`session:${userID}`)
           return await reply(messageID, '[COMMAND] Session reset successfully.')
+        } else if (content === '/help') {
+          return await reply(messageID, HELP_MESSAGE)
         } else if (content.match(/^\/img \S+/)) {
           const imageKey = await createImage(userID,
             content.replace(/^\/img /, ''))
@@ -260,5 +265,9 @@ const eventDispatcher = new lark.EventDispatcher({
 server.on('request',
   lark.adaptDefault('/event', eventDispatcher, { autoChallenge: true }))
 
-server.listen(env.PORT)
+server.listen({
+  host: env.LISTEN_IP,
+  port: env.PORT
+})
+
 console.info(`[${env.LARK_APP_NAME}] Now listening on port ${env.PORT}`)