Rephrasy

Rephrasy MCP Server

Use Rephrasy from Claude, Cursor, or any MCP client: humanize AI-generated text and images, and check AI-detection scores, without leaving your editor or agent workflow.

Four tools, one API key:

Tool	What it does
humanize	Rewrites AI-generated text in a natural, human style while preserving meaning
detect	Scores how likely a text is to be flagged as AI-written (overall + optional per-sentence)
humanize_image	Humanizes a local or remote image and saves the result next to the original
get_image_result	Collects an image that was still processing (free)

Setup

1. Get an API key — sign in at rephrasy.ai → Account → API. Both tools bill against your Rephrasy plan.

2. Add the server to your client:

Claude Code

claude mcp add rephrasy -e REPHRASY_API_KEY=<your-key> -- npx -y @rephrasy/mcp

Claude Desktop

Add to claude_desktop_config.json (Settings → Developer → Edit Config):

{
  "mcpServers": {
    "rephrasy": {
      "command": "npx",
      "args": ["-y", "@rephrasy/mcp"],
      "env": { "REPHRASY_API_KEY": "<your-key>" }
    }
  }
}

Cursor

Add to .cursor/mcp.json (project) or ~/.cursor/mcp.json (global):

{
  "mcpServers": {
    "rephrasy": {
      "command": "npx",
      "args": ["-y", "@rephrasy/mcp"],
      "env": { "REPHRASY_API_KEY": "<your-key>" }
    }
  }
}

Until the package is on npm you can run it straight from GitHub: replace "args": ["-y", "@rephrasy/mcp"] with "args": ["-y", "github:rephrasyai/rephrasy-mcp"].

Hosted server (no install)

Rephrasy also runs a hosted MCP server, so clients that speak streamable HTTP need nothing installed locally:

claude mcp add rephrasy https://v2-humanizer.rephrasy.ai/mcp -t http \
  -H "Authorization: Bearer <your-key>"

It supports OAuth as well — ChatGPT and other clients that require it discover it from the server and send you through a one-time consent page, so the key never reaches the client. The hosted server carries a wider tool set (engine recommendations, readability, bring-your-own-key detectors). Full docs: https://rephrasy.ai/mcp.

Tools

humanize

Parameter	Type	Required	Description
text	string	yes	The text to humanize
model	string	no	Rephrasy model, default "v4" (recommended). See Models
language	string	no	Output language hint (e.g. "en", "de"); defaults to input language

Returns the rewritten text plus the number of words charged.

Models

model	When to use it
v4	Default and recommended. Natural rhythm and sentence variety, length close to the source.
superstealth	Newest. Built for the highest bypass rates, recommended against Pangram. Slower: 10–60 s per request.
ft_clean-v3	Highest meaning retention and near-identical length — technical writing and anything with figures.
Undetectable Model	Best against academic detectors.
SEO Model	Simple, informal phrasing built around keywords.
<writing style id>	Rewrites in one of your saved Writing Styles.

v3 and Undetectable Model v2 are retired. Old calls keep working: the API routes v3 to superstealth and v2 to v4. The v3-only style parameter is gone.

detect

Parameter	Type	Required	Description
text	string	yes	The text to score (max 15,000 characters)
per_sentence	boolean	no	If true, also returns a score per sentence

Returns JSON with scores.overall (lower = more human-like) and, in per-sentence mode, sentences.

humanize_image

Parameter	Type	Required	Description
path	string	one of	Local image file (PNG, JPEG or WEBP, max 4 MB)
url	string	one of	Or an http(s) link to the image
quality	string	no	"standard" (default, usually under a minute) or "hq" (about 4 minutes)
output_path	string	no	Where to save the result; defaults to <name>-humanized.<ext> next to the input

A diffusion pass removes invisible AI watermarks such as SynthID while subject, composition and resolution stay the same. Costs 10 credits on standard and 20 on hq; a failed image is refunded. Standard images are usually saved within the call. If a job is still running, the tool returns a job_id instead.

get_image_result

Parameter	Type	Required	Description
job_id	string	yes	The job_id from humanize_image
output_path	string	no	Where to save the result

Waits up to about 50 seconds per call and saves the image once it is done. Results stay available for 72 hours and also show up in your image history on rephrasy.ai.

Example prompts

• "Humanize this paragraph, then run detect on the result to verify it."
• "Humanize this essay with superstealth so it passes Pangram."
• "Rewrite my draft with the humanize tool using model <style-id> (my writing style)."
• "Check which sentences of this post read as AI-written."
• "Humanize ~/Desktop/hero.png in hq and tell me where you saved it."

Development

npm install
npm run build
REPHRASY_API_KEY=<key> node dist/index.js   # runs on stdio

License

MIT © Rephrasy