How to Fix Notion MCP Missing in Claude Code When Using ModelArk on Windows

✓ Verified Fix

If you use Claude Code with multiple providers — Claude Pro and ModelArk — you might notice that Notion appears when using your Anthropic subscription but vanishes when launching Claude Code through ModelArk. The confusing part is that other MCP servers keep working normally. In this case, Playwright and claude-mem remained connected while Notion disappeared from the MCP list entirely.

The error messages that give it away:

Remote Control requires claude.ai subscription auth.
ANTHROPIC_AUTH_TOKEN is set, so this session is using API-key auth
✓ claude.ai OAuth token present
✗ claude.ai subscriber auth active

You may also see only local MCPs listed:

playwright · ✔ connected · 23 tools
plugin:claude-mem:mcp-search · ✔ connected · 21 tools

while Notion is missing entirely.


Why Notion disappears when using ModelArk

Claude Code supports two different types of integrations: Claude.ai cloud connectors and local or user MCP servers.

When you launch Claude Code with your Claude Pro subscription, cloud connectors attached to your Claude.ai account are available. When you launch Claude Code using ModelArk, Claude Code switches into API-key mode:

Auth token: ANTHROPIC_AUTH_TOKEN
Anthropic base URL: https://ark.ap-southeast.bytepluses.com

In API-key mode, Claude.ai cloud connectors are unavailable. If your Notion integration exists only as a Claude.ai connector, it disappears when you switch providers.

The fix is to install the official Notion MCP as a user-level MCP server instead of relying on the Claude.ai connector.


Step 1: Verify whether Notion is installed as a user MCP

Run:

claude mcp list

Expected output:

notion: https://mcp.notion.com/mcp (HTTP) - ✔ Connected

If Notion does not appear, install it:

claude mcp add --transport http notion https://mcp.notion.com/mcp --scope user

This creates a user-level MCP available across all Claude Code projects.


Step 2: Confirm the MCP is connected

claude mcp get notion

Expected output:

notion:
  Scope: User config (available in all your projects)
  Status: ✔ Connected
  Type: http
  URL: https://mcp.notion.com/mcp

A connected status confirms the MCP itself is working.


Step 3: Check your MCP configuration

Inspect the Claude configuration file:

Get-Content $HOME\.claude.json

Look for:

"mcpServers": {
  "notion": {
    "type": "http",
    "url": "https://mcp.notion.com/mcp"
  }
}

This confirms Claude Code is loading Notion as a user MCP rather than relying on the Claude.ai connector.


Step 4: Verify Notion appears inside ModelArk sessions

Launch Claude Code through ModelArk:

cark

Open the MCP manager:

/mcp

Expected result:

User MCPs (C:\Users\YOURNAME\.claude.json)

notion · ✔ connected · 14 tools
playwright · ✔ connected
plugin:claude-mem:mcp-search · ✔ connected

Notion now works regardless of which backend Claude Code is using.


Step 5: Verify your provider switching workflow

A clean provider-switching setup prevents ModelArk environment variables from leaking into future Claude Pro sessions:

function Clear-ClaudeProvider {
    Remove-Item Env:ANTHROPIC_BASE_URL -ErrorAction SilentlyContinue
    Remove-Item Env:ANTHROPIC_AUTH_TOKEN -ErrorAction SilentlyContinue
    Remove-Item Env:ANTHROPIC_MODEL -ErrorAction SilentlyContinue
}

function cpro {
    Clear-ClaudeProvider
    claude @args
}

function cark {
    Clear-ClaudeProvider

    $env:ANTHROPIC_BASE_URL = "https://ark.ap-southeast.bytepluses.com/api/coding"
    $env:ANTHROPIC_AUTH_TOKEN = $env:MODELARK_API_KEY
    $env:ANTHROPIC_MODEL = "ark-code-latest"

    try {
        claude @args
    }
    finally {
        Clear-ClaudeProvider
    }
}

FAQ

Why does Notion work with Claude Pro but not ModelArk? Claude Pro loads Claude.ai cloud connectors. ModelArk uses API-key authentication and does not load Claude.ai cloud integrations.

Do I need to reauthorize Notion when switching providers? No. Once the Notion MCP shows Status: ✔ Connected it works across providers without reauthorization.

Can I use Notion with Claude Pro, ModelArk, and OpenRouter simultaneously? Yes. User-level MCPs work independently of the backend provider.

Why does Playwright still work when Notion disappears? Playwright is configured as a local MCP server. It does not depend on Claude.ai account integrations.


Errors you can safely ignore

This message does not indicate an MCP failure — it only means Claude Code is operating in API-key mode rather than Claude.ai subscription mode:

Remote Control requires claude.ai subscription auth.
ANTHROPIC_AUTH_TOKEN is set, so this session is using API-key auth

This message refers to Claude.ai cloud features, not local MCP connectivity:

✗ claude.ai subscriber auth active

After switching to ModelArk you may also notice a brief terminal window that flashes and disappears. This is Playwright MCP launching through npx — Windows spawns a console window momentarily while npx starts the MCP process. It is cosmetic and does not affect MCP functionality. You can confirm it by inspecting running processes:

Get-CimInstance Win32_Process |
Where-Object { $_.Name -in @('node.exe','python.exe','pwsh.exe') } |
Select-Object ProcessId, Name, CommandLine |
Format-List

The output will include npx @playwright/mcp@latest — that’s the flash source.


Tested on: Windows 11 Pro, Claude Code 2.1.169, ModelArk Coding Plan, Notion MCP, Playwright MCP, Claude Mem MCP. Active troubleshooting time: approximately 45 minutes. Tools used: Claude Code, PowerShell, MCP Manager, Notion MCP, ModelArk API.