@elizaos/plugin-line

LINE Messaging API plugin for ElizaOS agents. Enables chatbot integration with LINE, a popular messaging platform in Japan, Taiwan, and Thailand.

Features

Text Messages: Send and receive text messages
Rich Messages (Flex): Create visually rich card messages
Location Messages: Share locations with map pins
Quick Replies: Provide suggested reply options
Group/Room Support: Operate in groups and multi-user rooms
User Profiles: Access user display names, pictures, and language
Webhook Integration: Receive messages via LINE webhooks

Installation

bash

# npm
npm install @elizaos/plugin-line

# bun
bun add @elizaos/plugin-line

Configuration

Environment Variables

Variable	Description	Required
`LINE_CHANNEL_ACCESS_TOKEN`	Channel access token from LINE Developers Console	Yes
`LINE_CHANNEL_SECRET`	Channel secret for webhook verification	Yes
`LINE_WEBHOOK_PATH`	Webhook endpoint path	No
`LINE_DM_POLICY`	DM policy: open, pairing, allowlist, disabled	No
`LINE_GROUP_POLICY`	Group policy: open, allowlist, disabled	No
`LINE_ALLOW_FROM`	Comma-separated user IDs for allowlist	No
`LINE_ENABLED`	Enable/disable the plugin	No

Agent Configuration

json

{
  "plugins": ["@elizaos/plugin-line"],
  "pluginParameters": {
    "LINE_CHANNEL_ACCESS_TOKEN": "your-channel-access-token",
    "LINE_CHANNEL_SECRET": "your-channel-secret",
    "LINE_DM_POLICY": "pairing",
    "LINE_GROUP_POLICY": "allowlist"
  }
}

Setup

Create a LINE Developers account at https://developers.line.biz/
Create a new Messaging API channel
Get your Channel Access Token (issue a long-lived token)
Get your Channel Secret
Set up webhook URL pointing to your server

Usage

Actions

LINE messaging routes through the canonical MESSAGE action using source: "line".

Primary action	Operation	Description
`MESSAGE`	`send`	Send text, flex, or location content to a user, group, or room
`MESSAGE`	`read_channel`	Read recent LINE conversation history when available
`MESSAGE`	`list_channels`	List recent LINE targets when available

Providers

LINE does not register standalone planner providers. Chat and user context is exposed through the LINE message connector hooks.

LINE ID Formats

User IDs: Start with U followed by 32 hex characters (e.g., U1234567890abcdef1234567890abcdef)
Group IDs: Start with C followed by 32 hex characters
Room IDs: Start with R followed by 32 hex characters

Message Limits

Text messages: 5000 characters max
Alt text (for flex/template): 400 characters max
Location title/address: 100 characters max
Messages per push: 5 max (batched automatically)

Webhook Setup

Configure your webhook URL in the LINE Developers Console
Ensure your server verifies webhook signatures using the channel secret
The plugin provides middleware for Express-style webhook handling

typescript

import { LineService } from "@elizaos/plugin-line";

// Get the middleware
const middleware = lineService.createMiddleware();

// Use with Express
app.post("/webhooks/line", middleware, async (req, res) => {
  const events = req.body.events;
  await lineService.handleWebhookEvents(events);
  res.status(200).end();
});

Flex Messages

LINE Flex Messages allow rich visual content. The plugin supports creating info card bubbles:

typescript

const flexMessage = {
  altText: "Update Notification",
  contents: {
    type: "bubble",
    body: {
      type: "box",
      layout: "vertical",
      contents: [
        { type: "text", text: "Title", weight: "bold", size: "xl" },
        { type: "text", text: "Body content", margin: "md", wrap: true }
      ]
    }
  }
};

Security Policies

DM Policies

Policy	Description
`open`	Accept DMs from anyone
`pairing`	Accept DMs and remember senders
`allowlist`	Only accept from LINE_ALLOW_FROM list
`disabled`	Don't accept any DMs

Group Policies

Policy	Description
`open`	Respond to anyone in groups
`allowlist`	Only respond to allowed users
`disabled`	Don't respond in groups

Development

Building

bash

cd typescript && npm run build

Testing

bash

npm test

API Reference

LineService

Methods

isConnected(): Check connection status
getBotInfo(): Get bot profile
sendMessage(to, text, options?): Send text message
sendFlexMessage(to, flex): Send flex message
sendTemplateMessage(to, template): Send template message
sendLocationMessage(to, location): Send location
replyMessage(replyToken, messages): Reply using token
getUserProfile(userId): Get user profile
getGroupInfo(groupId): Get group info
leaveChat(chatId, chatType): Leave group/room

License

MIT