@gutchain/mcp

An MCP server that lets a Claude agent push an article + image into a platform draft (Xiaohongshu / Douyin / WeChat) using the user's logged-in browser, via the Gutchain browser extension.

The server never touches the platforms directly. It hands the content to the extension over a localhost WebSocket; the extension reuses its existing draft-filling pipeline (open the creator page, upload the image, fill title and body) so the user only has to review and publish.

Claude agent ──(MCP stdio)──→ @gutchain/mcp ──(ws://127.0.0.1)──→ extension ──→ platform draft

Setup

1. Install the Gutchain extension in Chrome and log in to the target platforms.
2. Start the MCP server (see config below). On startup it prints a token to stderr.
3. Open the extension options → MCP Bridge, paste the token, set the port, and enable the bridge.

Tool

gutchain_share

| arg | type | notes | | -------------- | -------------------------------------- | -------------------------------------------------- | | image | string (required) | data URL, local file path, or raw base64 | | targets | ("xhs" \| "douyin" \| "wechat")[] | required, at least one | | title | string | optional; derived from text if omitted | | body | string | optional; falls back to text | | text | string | source text used to derive title/body | | authorName | string | optional | | authorHandle | string | optional | | imageMimeType| string | hint when image is bare base64 (default png) |

Config (env vars)

| var | default | meaning | | ----------------------- | -------------- | -------------------------------- | | GUTCHAIN_BRIDGE_PORT | 8765 | localhost WebSocket port | | GUTCHAIN_BRIDGE_TOKEN | random per run | set a fixed token to avoid repaste |

Claude Code (local dev, before publishing)

Build first:

pnpm --filter @gutchain/mcp build

Register with the Claude Code CLI (run once; --scope user makes it available in all projects):

claude mcp add gutchain --scope user \
  --env GUTCHAIN_BRIDGE_PORT=8765 \
  --env GUTCHAIN_BRIDGE_TOKEN=my-dev-secret \
  -- node /Users/xuxinyu/projects/web/gutchain-web/packages/mcp/dist/index.js

Verify it was added:

claude mcp list

To remove:

claude mcp remove gutchain --scope user

Claude Desktop / Claude config (after publishing to npm)

{
  "mcpServers": {
    "gutchain": {
      "command": "npx",
      "args": ["-y", "@gutchain/mcp"],
      "env": {
        "GUTCHAIN_BRIDGE_PORT": "8765",
        "GUTCHAIN_BRIDGE_TOKEN": "choose-a-stable-secret"
      }
    }
  }
}

Security

• The WebSocket binds to 127.0.0.1 only.
• The extension must present the shared token before any share request is accepted. Set a stable GUTCHAIN_BRIDGE_TOKEN so you paste it once.