Rephrasy MCP Server

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

Two 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)

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

Terminal

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):

config.json

{
  "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):

config.json

{
  "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"].

Tools

`humanize`

Parameter	Type	Required	Description
`text`	string	yes	The text to humanize
`model`	string	no	Rephrasy model, default `"v3"`
`style`	string	no	Writing-style ID from your account to mimic a specific voice
`language`	string	no	Output language hint (e.g. `"en"`, `"de"`); defaults to input language

Returns the rewritten text plus the number of words charged.

`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.

Example prompts

"Humanize this paragraph, then run detect on the result to verify it."
"Rewrite my draft with the humanize tool using my writing style <style-id>."
"Check which sentences of this post read as AI-written."

Development