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OpenAI

Humanize AI text inside ChatGPT

ChatGPT drafts beautifully and humanizes nothing. Add SupWriter as a custom connector — via ChatGPT's Developer mode — and call the humanizer, paraphraser, grammar checker, and AI detector as tools without leaving the chat. Custom connectors need a paid plan (Plus, Pro, Business, Enterprise, or Edu) and the ChatGPT web app.

https://supwriter.com/api/mcpOAuth sign-in · uses your plan credits

How to connect

Connect ChatGPT with a one-time OAuth sign-in — calls use your existing plan credits.

Recommended

Sign in with OAuth

  1. 1

    Turn on Developer mode

    In ChatGPT on the web, open Settings → Apps & Connectors → Advanced settings, and toggle Developer mode on. (This is the menu that older builds label simply "Connectors".)

  2. 2

    Create a custom connector

    Back on Apps & Connectors, click Create. Name it "SupWriter", paste https://supwriter.com/api/mcp as the MCP Server URL, set Authentication to OAuth, tick "I trust this application", and click Create.

  3. 3

    Sign in & approve

    A SupWriter window opens. Sign in and approve the consent screen — ChatGPT registers itself automatically, so there's no client ID or secret to copy.

  4. 4

    Enable it for the chat

    In the message composer, open the + (or Developer mode) menu and switch SupWriter on for the conversation — connectors are enabled per-chat.

  5. 5

    Use it

    Ask: "Humanize the draft above with a professional tone." ChatGPT shows each tool call for you to Confirm before it runs.

Test it

Once connected, ask ChatGPT to use a tool. A few prompts that work well:

  • “Humanize this so it reads naturally: <your text>”
  • “Paraphrase this in a casual tone: <your text>”
  • “Grammar-check and fix this paragraph: <your text>”
  • “Run an AI-detection check on the text above and tell me which sentences look AI-written.”

FAQ

Why do I need Developer mode?

Custom MCP connectors live behind ChatGPT's Developer mode (Settings → Apps & Connectors → Advanced settings) and require a paid plan — Plus, Pro, Business, Enterprise, or Edu. It's a beta feature and isn't available on the Free plan or in the mobile apps yet. On Business/Enterprise, a workspace admin can turn Developer mode off for everyone.

Does connecting cost anything extra?

No separate MCP fee — calls draw on the word credits already in your SupWriter plan (one credit per word). AI detection is metered over MCP too (one credit per word analyzed), the same as the REST API; it's free only inside the web app.

Is my account safe?

Yes. You authorize either through SupWriter's own OAuth sign-in — approving a consent screen that lists exactly what the client can do — or with a scoped API key. OAuth tokens are short-lived, and keys can be rotated or revoked any time from Settings → API & MCP.

Which tools become available?

Four: humanize, paraphrase, grammar-check, and AI detection — the same engines that power the SupWriter editor.

Want the full walkthrough with screenshots?

Read the ChatGPT setup guide