How to add an MCP server to ChatGPT

01Which way should I add an MCP server to ChatGPT?

02Which ChatGPT plans support custom MCP servers?

From OpenAI's help article on custom MCP servers and the ChatGPT pricing page. "Full MCP" means tools can also write or change data.

03Do I need developer mode to add an MCP server?

No. OpenAI's help article says you don't need to turn on developer mode first. You add the server from Plugins and accept a risk warning for each one. On Enterprise and Edu, an admin has to give you the Create plugins with MCPs permission.

04How do I add a remote MCP server to ChatGPT?

From OpenAI's custom MCP server guide:

1. Open Plugins. Go to chatgpt.com/plugins on the web.
2. Start a new server. Click +, then Add custom MCP server.
3. Name it. A description is optional.
4. Enter the address. Under Connection, paste the server's public HTTPS URL. It usually ends in /mcp.
5. Choose sign-in. Pick OAuth, No authentication or OAuth or no authentication.
6. Accept the warning. Tick I understand and want to continue.
7. Create it. Click Create as a plugin, then check the tools ChatGPT found.
8. Install the plugin. It has to be installed before you can use it.

To use it, start a new chat, type @ and pick the plugin. The pick applies to that one message, so @mention it again when a follow-up needs new data.

Which sign-in should I choose?

ChatGPT can't send API keys, client credentials or certificates (OpenAI). OAuth needs PKCE with S256. Your login provider should also issue refresh tokens, usually through the offline_access scope, or people have to sign in again when their first sign-in expires. Setup with Auth0, Okta, Clerk or Supabase: MCP server authentication.

Why does ChatGPT ask before using a tool?

Tools that write need your confirmation by default. ChatGPT treats any tool without the readOnlyHint annotation as a write action. You can remember a yes or no for a tool within one conversation, and a new chat asks again.

05How do I add an MCP server to the ChatGPT desktop app?

From OpenAI's MCP docs:

1. Open the settings. Go to Settings > MCP servers.
2. Add it. Click Add server.
3. Fill in the server. Enter a name, choose STDIO for a local command or Streamable HTTP for an address, and enter the command or URL.
4. Save and restart. Click Save, then Restart.
5. Sign in if needed. Click Authenticate next to a server that uses OAuth.

Type /mcp in the message box to see which servers are connected. A local server added here works only in the desktop app, not on the web or mobile.

The desktop app shares this setup with the Codex CLI and IDE extension. It lives in ~/.codex/config.toml, which you can also edit by hand:

[mcp_servers.files]
command = "npx"
args = ["-y", "@modelcontextprotocol/server-filesystem", "/Users/you/Documents"]

[mcp_servers.example]
url = "https://mcp.example.com/mcp"
bearer_token_env_var = "EXAMPLE_TOKEN"

Or add one from the Codex CLI, and sign in to it:

codex mcp add example --url https://mcp.example.com/mcp
codex mcp login example

06Can I add a local MCP server to ChatGPT?

Not on the web, which connects only to remote servers. You have three options:

Secure MCP Tunnel runs a small program, tunnel-client, on a machine that can reach your server. It only makes outgoing connections to OpenAI, so you open no firewall ports.

1. Create a tunnel. In OpenAI Platform settings, open Tunnels and note the tunnel_id. You need the Tunnels Read and Manage permissions.
2. Install tunnel-client. Get the latest release from openai/tunnel-client and a runtime API key.
3. Point it at your server. Run tunnel-client init with the tunnel ID and either --mcp-command for a local command or --mcp-server-url for an address. Then run tunnel-client run --profile <name> and keep it running.
4. Add it in ChatGPT. In Plugins, choose Add custom MCP server, select Tunnel under Connection and pick your tunnel.

The tunnel has to be linked to the ChatGPT workspace that should see it. A server behind a tunnel can't be submitted to the public plugin directory.

07How do Business and Enterprise admins control MCP servers?

Admins set these under Workspace settings > Permissions & roles (OpenAI):

Share plugins and Publish plugins to workspace control who can share a plugin and list it in the workspace directory. On Enterprise and Edu, admins can give each permission to chosen roles.

To publish a tested server for everyone in the workspace:

1. Open the draft. In Admin console, pick the workspace, open Plugins, select Manage Legacy Apps, then Drafts.
2. Publish it. Click Publish and read the safety warnings, especially for write actions.
3. Limit it (Enterprise and Edu). Use Configure Actions to choose which actions it may take and Configure Access to choose groups.

Members then find it under Settings > Plugins. After approval, ChatGPT keeps a frozen copy of the tool list. Changes to the server don't apply until an admin refreshes it. If the live server stops matching that copy, calls can fail, and admins aren't notified.

08Why is my ChatGPT MCP server not working?

From OpenAI's connect and test guide, sign-in guide and troubleshooting article:

To test a server's address without ChatGPT, paste it into the free MCP directory check.

09How do I make my MCP server available to every ChatGPT user?

A custom MCP server works only for you, or for your workspace once an admin publishes it. The workspace directory isn't the public one.

To appear for every ChatGPT user, submit the server for review at platform.openai.com/plugins. OpenAI's submission guide asks for a verified organization, a stable public HTTPS endpoint and a token served at /.well-known/openai-apps-challenge. Local servers and desktop-only plugins have a separate desktop-only submission. Checklist, review and timeline: ChatGPT's plugin directory.

10Does the same MCP server work in Claude?

Yes. In Claude, add the same URL as a custom connector under Customize > Connectors > + Add > Add custom connector. Every Claude plan can add one, and Free is limited to one (Anthropic). Claude also connects from the cloud, so the server must be public there too.

Sign-in works differently in a few places: where ChatGPT and Claude differ. Full steps: how to add an MCP server to Claude.

12Common questions