line-mcp

What you can ask

Once it's connected, just talk to Claude:

• "What did I miss on LINE today?"

• "Summarize the family group chat from this week."

• "Find the message where Sarah sent the restaurant address."

• "Show me the photo Ken sent this morning." (encrypted images are decrypted)

• "Has everyone in the team group read my last message?"

• "Reply 'on my way 🙏' to Mai's last message." (Claude asks you first)

• "Wait for a reply from the landlord and tell me when it comes."

Related MCP server: yomi

Features

• 💬 Chats & messages. Contact and group names, sender names (even for group members who aren't your friends), replies, stickers, files, locations, and paging back through history.

• 🔐 End-to-end encryption. Letter Sealing messages and media are decrypted locally, including the messages you sent yourself.

• 🔎 Instant search. A local store of every message the server has seen. Substring search works for Thai, Japanese and other scripts without word spacing.

• ⚡ Real time. Subscribes to LINE's operation stream (like the Chrome extension does) for new messages, unsends and read notices, and catches up after a restart.

• ✍️ Acting as you. Text, replies, photos, videos, files, voice messages, stickers, reactions, unsend and mark-read. All of these are flagged as write tools, so your client asks before using them.

• 👀 Read receipts. Who has read what, and when.

• 🔑 Login from the chat. When the session expires, Claude shows the QR code right in the conversation.

• 🛡️ Careful by default. About 4 requests per second, at most 10 outgoing actions per minute, key caching, and secrets stored 600.

Quick start

You need Node.js 18+ installed (LINE's request signing runs in it). Then pick the option that fits how you work.

Option 1: Claude Desktop, one click

1. Download line-mcp.mcpb and double-click it. Claude Desktop installs everything, including Python.

2. In a new chat, say "log me in to LINE". Claude shows a QR code; scan it with LINE on your phone (Home → QR scanner), then type the PIN Claude gives you.

That's it, no terminal needed.

Option 2: any app, one command

uv tool install git+https://github.com/itsloukman/line-mcp   # or: pipx install git+https://github.com/itsloukman/line-mcp
line-mcp setup

setup checks Node, logs you in (QR in the terminal), detects your MCP apps and adds itself to the ones you choose. It supports Claude Desktop, Claude Code, OpenAI Codex, Cursor, Windsurf, VS Code and Gemini CLI. Existing config files are merged, never overwritten, and backed up as *.bak-line-mcp.

To target specific apps later:

line-mcp install codex cursor      # or: --all
line-mcp uninstall cursor
line-mcp install --print           # print a JSON snippet for any other client

Option 3: configure by hand

Each snippet uses uvx to run straight from GitHub, so there's nothing to install except uv. Log in first with uvx --from git+https://github.com/itsloukman/line-mcp line-mcp login, or ask your assistant to "log me in to LINE".

claude mcp add --scope user line-personal -- uvx --from git+https://github.com/itsloukman/line-mcp line-mcp serve

[mcp_servers.line-personal]
command = "uvx"
args = ["--from", "git+https://github.com/itsloukman/line-mcp", "line-mcp", "serve"]

Paste into claude_desktop_config.json, ~/.cursor/mcp.json, ~/.codeium/windsurf/mcp_config.json or ~/.gemini/settings.json:

{
  "mcpServers": {
    "line-personal": {
      "command": "uvx",
      "args": ["--from", "git+https://github.com/itsloukman/line-mcp", "line-mcp", "serve"]
    }
  }
}

GUI apps start servers with a minimal PATH. If yours can't find uvx, use its absolute path (which uvx).

{
  "servers": {
    "line-personal": {
      "type": "stdio",
      "command": "uvx",
      "args": ["--from", "git+https://github.com/itsloukman/line-mcp", "line-mcp", "serve"]
    }
  }
}

Tools

Read tools carry readOnlyHint, so clients can auto-approve them. Everything that acts as you is a write tool, so the client asks first. Tools run in worker threads, so a slow search or wait never blocks the others.

line_login_start returns the QR code as an image in the chat. line_login_status reports progress and gives the PIN to type on your phone. Logging in again usually skips the PIN.

How it works

flowchart LR
    C["Claude / any MCP client"] <-- "stdio (MCP)" --> S["line-mcp serve"]
    S <-- "HTTPS, X-Hmac signed" --> G["LINE Chrome gateway"]
    G -- "SSE operation stream" --> S
    S --- N["Node bridge<br/>(LINE's LTSM WASM:<br/>signing + E2EE keys)"]
    S --- D[("~/.line-mcp<br/>session.json · messages.db")]

• Login replays the LINE Chrome extension's QR flow. Your phone approves this computer as a companion device and hands it the Letter Sealing keychain, which is stored in session.json.

• Requests are signed by LINE's own WASM module, run in a small Node.js process. That's why Node is required.

• E2EE messages are decrypted locally. Media is downloaded and decrypted the same way the extension does it (HKDF → AES-CTR plus an HMAC check).

• Live sync follows LINE's operation stream, saving its position so it can resume after a restart. A once-a-minute check fills the gaps, such as messages you send from your phone.

Privacy & safety

• Everything stays on your machine. There's no third-party server; the only network traffic goes to LINE.

• ~/.line-mcp/ holds secrets. session.json has your tokens and E2EE private keys, and messages.db has decrypted message text. Both are created mode 600 in a 700 directory. Never commit or share them.

• Don't want a local copy? Set LINE_MCP_STORE=off to disable the message store. You lose search history, new-message queries and waiting.

• For agent builders: treat every write tool as acting in the user's name. Get explicit approval of the exact text or action, every time.

Configuration

Troubleshooting

Run line-mcp doctor first. It checks Node, the session file and its permissions, the login, the E2EE keys and the store.

Limits

• History: LINE serves a companion device only about the last two weeks of history. Anything older is only searchable if the store saw it while it was recent.

• Stickers: you can only send stickers from packs you own.

• Groups: okline can't create a group's first E2EE key, so sending into a sealed group that has never had an encrypted message may fail.

• okline version: pinned to <2.8, because this server patches parts of okline's E2EE internals.

Development

# build the Claude Desktop extension: npx @anthropic-ai/mcpb pack . dist/line-mcp.mcpb

git clone https://github.com/itsloukman/line-mcp && cd line-mcp
uv venv venv && uv pip install -p venv/bin/python -e '.[test]'
venv/bin/python -m pytest -q        # offline tests, no LINE account needed

Credits & license

MIT. Built on okline; check its license and terms too. LINE is a trademark of LY Corporation. This project is not affiliated with it, and the logo is original artwork.