Why can't I find Developer Mode in ChatGPT?

Developer Mode is documented in two places, so check both before concluding it is missing: Settings then Apps then Advanced Settings, and Settings then Security and login then Developer mode, with custom apps created from chatgpt.com/plugins. It needs a paid plan — Plus, Pro, Business, Enterprise, or Edu, not Free. It is also web only, so you won't see it in the ChatGPT mobile apps. On Business, developer mode is for workspace admins and owners, and each admin turns it on for themselves. On Enterprise or Edu, an admin first grants access under Workspace Settings, Permissions & Roles, Connected Data, and then the toggle appears for you.

Is the orange border around ChatGPT a problem?

No. The orange border just means Developer Mode is active, which is required for custom MCP apps. It isn't a jailbreak or a warning, and it is expected while you have a custom app connected.

How to Add a Custom MCP Server to ChatGPT

Q: Lookups work in ChatGPT but saves don't. Why?

That is usually ChatGPT's plan-level write gate. OpenAI's help centre documents full MCP support, including tools that save and update, for Business, Enterprise, and Edu workspaces, while its developer docs list Plus and Pro as eligible for full read and write. On Plus and Pro, lookups are the dependable part, and saves are worth testing. ChatGPT also asks you to confirm write actions by default, so check for a pending confirmation.

How do I add a custom MCP server to ChatGPT?

Enable Developer Mode under Settings → Apps → Advanced Settings, then Create App, paste the server's URL, leave Authentication set to OAuth, scan the tools, and create. Two constraints decide whether this is even possible for you: custom MCP apps need a paid plan and are web only — they don't run in the ChatGPT mobile apps.

What plan you need, and what it gets you

As of August 2026, custom MCP apps are available on Plus, Pro, Business, Enterprise, and Edu — not Free.

The plan also determines what the connection can do, which is the part people discover late:

OpenAI documents full MCP — tools that can save and update — for Business, Enterprise, and Edu workspaces.
Pro is described as connecting MCP servers with read and fetch permissions in developer mode.
Plus is the unclear one. OpenAI's help centre says full MCP is currently for Business, Enterprise, and Edu; its developer docs list Plus and Pro as eligible for full read and write. Expect lookups to work, and treat saves as something to try rather than count on.

So a connection where lookups work and saves do not run is usually not a broken integration. OpenAI documents that read-and-fetch limit for Pro. For Plus, OpenAI's two sources differ: its help centre says full MCP, including write actions, is currently for Business, Enterprise, and Edu, and its developer docs list Plus and Pro as eligible for full read and write — so treat saves on Plus as something to test rather than assume. ChatGPT also asks you to confirm write actions by default, and you can choose to remember your answer for the rest of that conversation, so a pending confirmation is a separate cause worth ruling out.

On Business, Developer Mode is for workspace admins and owners: it is enabled under Workspace Settings → Permissions & Roles → Connected Data, and each admin toggles it on for themselves. On Enterprise and Edu, an admin grants access there first, and enabled members then turn it on under Settings → Apps → Advanced Settings.

Enabling Developer Mode

Log in to ChatGPT on the web
Click your profile name or icon in the lower-left
Click Settings
Go to Apps — older versions label this "Apps & Connectors" or "Connectors"; OpenAI renamed connectors to apps in December 2025, then migrated the app directory to the Plugin directory on July 9, 2026, so current builds may show Plugins
Click Advanced Settings
Toggle Developer Mode on

If that path doesn't match what you see: OpenAI's developer documentation describes the toggle under Settings → Security and login → Developer mode, with custom apps created from chatgpt.com/plugins. Both paths have been documented during 2026 and the labels vary by account and build. Try the other one rather than concluding the feature is missing.

Creating the app

With Developer Mode on, go to Settings → Apps → Advanced Settings and click Create App. Fill in:

Icon — upload one to make the app easy to spot
Name — what you'll select in the chat menu
Description — optional
MCP Server URL — the server's endpoint
Authentication — leave the default set to OAuth
Check the "I understand" acknowledgment for custom MCP server risk
Click Scan Tools — current versions scan the server's tool list before creation. With OAuth, complete the authorization prompt first, then let the scan finish.
Click Create — the app appears with a "Dev" label, and may also be listed under a Drafts tab in your app settings. Workspace admins see it there until published.

Authorization

After creating the app, ChatGPT prompts you to authenticate: a browser window opens with the server's authorization page, you log in if prompted, review the permissions, and approve. You are redirected back to ChatGPT with the connection active.

Using it in a conversation

Custom apps are not automatically on in every chat:

Open a new chat
Click the + button in the chat input area
Click More
Select your app

On current builds, the + menu may show Developer mode instead of More. Choose it, then select your app.

Selecting the app applies to the message you send with it. If a later message needs fresh data from the app, @-mention it by name again. To refresh context entirely, start a new chat.

About that orange border

The orange border around the ChatGPT interface while Developer Mode is active is normal and expected. It is not a jailbreak, not a warning, and not a sign anything is misconfigured. Developer Mode is a beta feature for building and connecting custom MCP tools, and the border is simply its indicator.

What usually goes wrong

Problem	Fix
Developer Mode toggle not visible	Requires a paid plan (Plus and up). On Business, Developer Mode is for admins and owners; on Enterprise/Edu, an admin grants access first. Confirm you are on ChatGPT web — custom apps aren't available on mobile.
Saves don't run, lookups work	Usually the plan-level write gate. Full MCP write support is documented for Business, Enterprise, and Edu workspaces; OpenAI's developer docs also list Plus and Pro as eligible for full read and write, so test saves on those plans rather than assume them. ChatGPT also asks you to confirm write actions by default, so check for a pending confirmation.
The app is missing in agent mode or deep research	OpenAI documents that agent mode will not use custom apps at all, and that deep research can use them for read and fetch actions only, not writes. Use a normal chat for full tool access.
"Create App" not available	Developer Mode isn't toggled on in Advanced Settings.
Authorization doesn't complete	Clear browser cache and retry.
App not showing in chat menu	Click + → More, or + → Developer mode on current builds, to find it.
Context doesn't load	Start a new conversation with the app enabled.

A worked example

With a real server — Tempreon, a hosted MCP server that carries your context across every AI tool you connect:

https://api.tempreon.com/functions/v1/tempreon-mcp/mcp

Create the app with that URL, Authentication set to OAuth, and approve in the browser. The point of connecting a portable memory server here specifically is cross-provider reach: knowledge stored in a Claude session is available in ChatGPT and vice versa, with no manual syncing.

The account-holder walkthrough, with screenshots of each dialog, is in the ChatGPT setup doc.