weixin

WeChat Claude Relay

WeChat Claude Relay is a minimal WeChat channel plugin for Claude Code. It bridges WeChat iLink Bot messages into the current Claude Code session and lets Claude reply through one tool: send_message.

Scope

This project intentionally implements only:

Surface	Name	Purpose
MCP tool	send_message	Send text plus optional local files to a WeChat chat
Slash command	/login	QR-code login and credential storage

It does not include access control, pairing codes, allowlists, message history, approval forwarding, or QR-login MCP tools.

Prerequisites

• Bun 1.0+
• Claude Code with channel plugin support
• A WeChat account that can authorize the iLink Bot flow

Install

From this directory:

./install.sh

The installer installs dependencies, ensures the directory has a Git commit, registers the local marketplace, and installs weixin@wechat-claude-relay.

Manual equivalent:

bun install
git init
git add -A
git commit -m "initial local plugin"
claude plugin marketplace add /absolute/path/to/wechat-claude-relay
claude plugin install weixin@wechat-claude-relay

Login

In Claude Code, run:

/login

The command displays a QR code and saves credentials to:

~/.claude/channels/weixin/account.json

The credential file is written with 0600 permissions. The full token is never printed by the login helper. Useful variants:

/login status
/login relogin
/login clear

Start The Channel

After login, start Claude Code with the plugin channel enabled:

claude --channels plugin:weixin@wechat-claude-relay

If your Claude Code build requires the development-channel flag for local plugins, use the flag it prints in the terminal.

Inbound Messages

State lives in ~/.claude/channels/weixin/:

Path	Purpose
account.json	iLink login credential
context.json	Cached context_token by WeChat chat ID
sync_buf.txt	Long-poll get_updates_buf cursor
inbox/	Downloaded image and file attachments

Supported inbound item types:

Type	Handling
Text 1	Forwarded directly as channel content
Image 2	CDN download, AES-128-ECB decrypt, save to inbox/, path in metadata
Voice 3	Server transcript forwarded as text when present
File 4	CDN download, decrypt when keyed, save to inbox/, path in metadata
Video 5	Placeholder only

Tool

Claude receives a single tool:

{
  "name": "send_message",
  "arguments": {
    "chat_id": "user@im.wechat",
    "text": "hello",
    "files": ["/absolute/path/to/file.png"]
  }
}

chat_id comes from inbound channel metadata. The server uses the persisted context.json cache internally; callers do not pass context_token.

Development

Run type checks:

bun run check

Build bundled outputs:

bun run build

Run the no-model MCP smoke test:

bun run smoke:mcp

The smoke test starts the MCP server with a temporary HOME, performs an MCP initialize handshake, verifies that only send_message is exposed, and exits. It does not call Claude models or consume model tokens.