AI Humanizer MCP

Use Rephrasy where you already write — inside your AI assistant.

Add one URL as a connector and your assistant can rewrite drafts and score them for AI-written content mid-conversation. No SDK, no glue code, no second tab. Every call runs on your Rephrasy account and the credits you already have.

Connector URL

https://v2-humanizer.rephrasy.ai/mcp

Authenticate with the same Rephrasy API key you use for the REST API.

Works withClaudeChatGPTCursorClaude Code

What you can do with it

Four things people actually use it for, with the responses the tools really return.

You say

“Humanize this blog intro for me, it reads like a press release.”

Your assistant calls humanize_text

You get back

{
  "output": "Remote work didn't arrive gently. It landed in March 2020…",
  "engine": "v4",
  "report": {
    "words_in": 118,
    "words_out": 121,
    "length_ratio": 1.025,
    "figures_kept": ["2020", "42"],
    "figures_missing": [],
    "figures_added": [],
    "flesch_reading_ease": 68.4
  }
}

Every rewrite comes back with a preservation report: how the length moved, which figures survived, and which the rewrite lost or invented. You see what changed instead of trusting that nothing did.

And here it is running

A real conversation, not a mock-up: ChatGPT calls the connector over OAuth, rewrites the sentence with v4 and reports what survived — the figure 2024 kept, nothing lost or invented.

Set it up

One URL and your API key. Under a minute in any client.

1. 1Open Claude and go to Settings → Connectors → Add custom connector.
2. 2Name it Rephrasy and paste the connector URL. Leave the rest alone: Claude reads the authentication off the server itself and registers its own OAuth client.
3. 3Click Add, then Connect. Our page asks for your Rephrasy API key once and hands Claude a token; the key itself never reaches Claude.
4. 4The Rephrasy tools appear in your tool picker, ready to use in any chat.

Click a step to see that screen.

Your API key

Authorization: Bearer YOUR_API_KEY

The same key as the REST API — find it in your Rephrasy account. Claude and ChatGPT ask for it once on our consent page and get a token back, so the key stays with us. Claude Code and Cursor send it directly as the header above. Either way it is never part of a prompt.

Tools and pricing

Six tools. All need your Rephrasy account; two spend a credit, four do not.

Tool	Cost	What it does
humanize_text	1 credit	Rewrites a draft into natural prose. Takes a purpose (blog, marketing, seo, report, technical) and picks the engine for you, or name the engine yourself. Returns the rewrite plus a preservation report.
check_ai_score	1 credit	Scores text for AI-written content and returns the passages that scored highest, so you can see which parts to revise.
recommend_engine	No credit	Suggests the engine and voice for a kind of writing.
readability_score	No credit	Flesch reading-ease score for any text.
list_engines	No credit	Lists the engines, voices and detectors your connector can use.
credits_left	No credit	Tells you how many credits the connected account has left, and how many calls that buys. Every paid answer carries the same number, so the assistant can warn you before a long job runs dry.

Models

The same model names the REST API takes. Leave the choice to the purpose you give, or name one directly.

v4

v4 — the recommended default. Natural rhythm and sentence variety, length stays close to the source.

ft_clean-v3

ft_clean-v3 — the highest meaning retention (0.96 mean cosine on our benchmark against 0.92 for v4) and near-identical length. For technical writing and anything with figures.

v3

v3 — a voice-driven rewrite. Pick a style; 'creative' is the strongest and also the longest, so avoid it when length matters.

seo

seo — rewrites around the keywords you need to keep.

Detectors

The Rephrasy AI Detector works the moment you connect — no extra account, one flat credit per check. You can also run any other detector on your own key: add it to the connector as a request header and that provider bills you directly, with no Rephrasy credit charged.

Detector	Your key
Rephrasy AI Detector	Included — nothing to set up
wasitaigenerated.com	x-wia-key
GPTZero	x-gptzero-key
Winston AI	x-winston-key
Copyleaks	x-copyleaks-key + x-copyleaks-email
Pangram	x-pangram-key
ZeroGPT	x-zerogpt-key

Ask list_engines to see which detectors your connector can currently use. Pangram needs at least 100 words; Copyleaks at least 255 characters.

Get Started Now

Convert AI to Human Text — Free AI Humanizer

The #1 AI humanizer trusted by 125,000+ students & professionals