# ScriptGrain makes ChatGPT better at being you · ScriptGrain

> Connect ScriptGrain to ChatGPT: a measured 45-attribute profile of your voice, a score on every draft, and a polish toward the target. ChatGPT keeps doing what it does; it just sounds like you.

Canonical: https://scriptgrain.com/works-with/chatgpt

# ScriptGrain makes ChatGPT better at being you

*By Jack Stovell · published 2026-09-20*

ChatGPT can write for you. It cannot measure you. ScriptGrain measures your voice as 45 attributes from writing you have already published, connects to ChatGPT, and scores every draft against the measurement, so the assistant you already use writes as you rather than as its average.

**Start with the prompt builder below**: paste your writing and get a system prompt written in measured numbers, ready for custom instructions or a project. The connector does the same with the full profile.

## How to connect

Works with ChatGPT (chatgpt.com, the desktop and mobile apps).

1. **Measure your voice.** Create a free ScriptGrain account and paste three or more pieces you wrote (3,000 words works best). The profile takes a few minutes and costs nothing.
2. **Connect.** Add ScriptGrain as a connector in ChatGPT's settings (Connectors, then Add custom connector) with the MCP server URL `https://mcp.scriptgrain.com/mcp`, and sign in with your ScriptGrain account when the consent page opens. Where connectors are not available on your plan, paste the prompt the builder below produces into Custom instructions instead; it is the one-page version of the same measurement.
3. **Write, then score.** Ask ChatGPT for a draft and name the profile: "Write a LinkedIn post about X in my ScriptGrain voice." ChatGPT calls `generate_content`, or drafts itself and calls `check_voice_match` to score the result. Ask it to polish anything under 0.8.

## What changes

Without a profile, ChatGPT writes from a description: whatever you can say about your own style. Most of a voice is what you cannot say: contraction rate, clause ordering, how often you open with a question, the words you reach for without noticing. With ScriptGrain connected, ChatGPT writes from the measured profile and every draft comes back with a voice-match score and the exact features that moved. On-voice drafts score 0.85 to 0.95; a clearly different voice scores under 0.45. Paste any two pieces into the free off-voice check to see the same measurement with no account.

## What stays free

The profile, the connector, scoring any text against your profile, and comparing pieces with no profile at all are free on every plan. Generating drafts in your voice, polishing toward a target and the monthly voice monitor are paid.

## Questions

### Do I need a paid plan to connect ScriptGrain to ChatGPT?

No. The connector, the profile and voice-match scoring are on the Free plan. Paid plans add generation credits, polishing and the monthly voice monitor.

### Does ChatGPT send my conversations to ScriptGrain?

No. ChatGPT calls ScriptGrain only when it uses a tool (score this text, generate this brief), and ScriptGrain receives only what that call contains. Your API key or sign-in token never appears in the conversation.

### What is the voice-match score measuring?

Stylistic alignment: sentence rhythm, punctuation habits, pronoun mix, formality, argument structure and the rest of the measured attributes, compared feature by feature against your profile. It says whether the draft sounds like you, not whether it is any good.

## Related

- [AI writing API and MCP server](https://scriptgrain.com/ai-writing-api-and-mcp-server)
- [Free off-voice check](https://scriptgrain.com/tools/brand-voice-consistency-checker)
- [Make ChatGPT better at being you](https://scriptgrain.com/make-chatgpt-sound-like-you)