UiChemy MCP: Troubleshooting Guide

Troubleshooting: MCP Server Disconnected

The Problem

After saving your Claude Desktop config file correctly, you may still see one or both of
These errors in the Claude Desktop Developer settings:

• MCP demo-wordpress-uichemy-mcp: Server disconnected
• MCP uichemy-api-mcp: Server disconnected

This is almost always caused by a missing or outdated Node.js installation on your
machine. Claude Desktop requires NodeJS & NPX to connect to remote MCP Servers.

Root Cause

• Node.js is not installed
• Node.js is installed but running an outdated version
• NVM (Node Version Manager) is not installed

How to Fix It

Step 1 — Install Node.js

Visit the official Node.js website and download the installer for your operating system:
Download Node.js: https://nodejs.org/en/download
Available for: Windows, macOS, and Linux
Run the installer and follow the on-screen steps. Once complete, restart the Claude Desktop.

If you are still having issues, move on to Step 2.

Step 2 (Optional) — Install NVM (Node Version Manager)

Note: This is only needed if you are still seeing connection errors after completing Step 1 and Step 4.

NVM lets you manage and switch between Node.js versions easily. Even if Node.js is
already installed, NVM ensures you are running the correct version required by the
MCP Server.

For Windows:

1. Go to the NVM for Windows releases page:
   https://github.com/coreybutler/nvm-windows
2. Click Download Now, scroll down to Assets, and download nvm-setup.exe
3. Run nvm-setup.exe and complete the installation.

For macOS / Linux:
Run this command in your terminal:

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.4/install.sh | bash

Note: If you see “Profile not found” after running the above command, it means NVM could not automatically configure your shell. Run these two lines manually to load NVM in your current session:

export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"

To make it permanent, run echo $SHELL first to check your shell, then use the matching command:

For zsh (/bin/zsh):

echo 'export NVM_DIR="$HOME/.nvm"' >> ~/.zshrc && echo '[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"' >> ~/.zshrc && source ~/.zshrc

For bash (/bin/bash):

echo 'export NVM_DIR="$HOME/.nvm"' >> ~/.bashrc && echo '[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"' >> ~/.bashrc && source ~/.bashrc

Step 3 — Install and Use the LTS Version of Node.js

If Node.js is already installed on your system but the MCP servers are still not
connecting, it is likely running an outdated version. Run these two commands in your
terminal to switch to the LTS version:

nvm install 24
nvm use 24

Step 4 — Restart Claude Desktop

Fully quit Claude Desktop — not just close the window, actually quit the application.
Reopen it and wait for it to fully load.
Your MCP servers should now connect successfully.

You will see both listed under Connectors:

• WordPress MCP (your site)
• UiChemy API MCP

How to Use UiChemy MCP with HTTP Basic Authentication

If your WordPress website is protected with HTTP Basic Authentication (Basic Auth), you can still connect to UiChemy MCP without any issues.
This setup is commonly used for staging sites or protected production environments.

What is HTTP Basic Authentication?

HTTP Basic Authentication adds a username and password layer to your website before users can access it.

To allow UiChemy MCP to connect properly, you need to pass the Basic Auth credentials through the Claude Desktop MCP configuration.

Step 1: Generate the Basic Auth Header

First, generate your Authorization header using your Basic Auth username and password.

You can use any online Basic Auth Header Generator tool.

Example Output

Authorization: Basic YWJjZDpwdWVz

This generated header will be added to your MCP configuration in the next step.

Step 2: Open Claude Desktop MCP Configuration

Open the following file in Claude Desktop:

claude_desktop_config.json

Now, locate your UiChemy MCP configuration.

Step 3: Add the Authorization Header

Add the generated Basic Auth header inside the args section using –header.

Example Configuration

"uichemy-wordpress-uichemy-mcp": {

 "command": "npx",

 "args": [

   "-y",

   "mcp-remote",

   "https://your-site.com/wp-json/uichemy/v1/mcp",

   "--header",

   "UiChemy-Security-Token: YOUR-SECURITY-TOKEN",

   "--header",

   "Authorization: Basic YWJjZDpwdWVz"

 ]

}

Step 4: Save and Restart Claude Desktop

After updating the configuration:

1. Save the claude_desktop_config.json file
2. Restart Claude Desktop
3. Reconnect your UiChemy MCP server

Note: Make sure your Basic Auth username, password, security token, and site URL are correct. Keep your Authorization header private, and if the connection fails, regenerate the header and verify all credentials before reconnecting to the MCP server. 

Quick Summary

Step	Action
1	Download and install Node.js from nodejs.org/en/download
2 (Optional)	Download and install NVM — nvm-setup.exe (Windows) or via terminal (Mac/Linux)
3	Run: nvm install lts then nvm use lts
4	Fully quit and reopen Claude Desktop