Building with an AI agent? Copy the full API reference as Markdown, or point it at /llms.txt.

MCP Server

Use Phrasly Business from Claude, ChatGPT, Cursor and any MCP client.

Overview

The Phrasly Business MCP server brings the humanizer and the AI detector into AI assistants. Connect it once, and the assistant can humanize a draft, check text for AI writing and look up your balance without leaving the conversation.

Every call is billed to your account at its own rates, from the same credits as the REST API, with the same autopay and overage limit. Apps sign in with OAuth, so most of them need nothing but the URL below.

Server URL

A remote MCP server over Streamable HTTP. Paste it wherever your app asks for a server or connector URL.

https://business.phrasly.ai/mcp

Connect your app

Pick your app. Each one takes the URL or a single command, then one sign-in with your Phrasly Business account.

Open Settings, then Connectors
Click Add custom connector and name it Phrasly Business
Paste this URL
https://business.phrasly.ai/mcp
Click Connect, then approve access with your Phrasly Business account

Works in Claude on the web and in Claude Desktop. Custom connectors are available on Claude Pro and Max. On Team and Enterprise, an owner adds the connector once and members connect their own accounts.

Add a remote MCP server in your app and name it phrasly-business
Paste this URL
https://business.phrasly.ai/mcp
Sign in with your Phrasly Business account when the app asks. Apps that support OAuth register themselves, so there is no API key to copy

Works with any MCP client that supports remote servers. Apps that cannot sign in with OAuth can send an API key in the x-api-key header, or as a bearer token.

Tools

Ask in plain language: the assistant picks the tool and hands back the result. Apps that support MCP prompts also get two commands, humanize and check-ai (in Claude Code, type /mcp__phrasly-business to find them).

humanize_textHumanize text

Rewrites AI-generated text so it reads like a person wrote it, with the same engine as the Humanization API. Takes 20 to 5,000 words per call; the assistant splits longer documents into chunks.

text The text to humanize.
content_type Optional. What kind of text it is, for example "product description".

detect_ai_textCheck text for AI writing

Scores text with the Phrasly AI detector and returns the AI probability, the verdict, and the sentences that read as AI. Takes 50 or more words and up to 15,000 characters per call.

text The text to analyze.
content_type Optional. What kind of text it is.

get_account_statusAccount status

Whether requests are allowed right now (and why not), the credit balance, this billing period's usage and cost, the account's rates, autopay and the overage limit, and the API key the connection bills through. Free.

Accounts with Phrasly Ultra also get mode and the text settings on humanize_text, with the same values and prices as the Humanization API.

Authentication

OAuth (recommended)

Apps that support OAuth (Claude, ChatGPT, Claude Code, Cursor) only need the URL: they register themselves and send you to business.phrasly.ai to sign in with an emailed code and approve the connection. Team members can connect apps too; the calls bill the account.

Each connected app gets an API key of its own, named after the app, so its usage shows on the API Keys page.
Delete that key to disconnect the app. It is signed out on its next request.
Removing a team member signs out every app they connected, without touching the apps the owner or other members connected.
A connection lasts 30 days. After that the app asks you to sign in again and keeps the same key and usage history.

API key

Clients that can set headers can use one of your API keys instead, as x-api-key: YOUR_API_KEY or Authorization: Bearer YOUR_API_KEY. Usage counts against that key.

bash

claude mcp add --transport http phrasly-business https://business.phrasly.ai/mcp \
  --header "x-api-key: YOUR_API_KEY"

json

{
  "mcpServers": {
    "phrasly-business": {
      "url": "https://business.phrasly.ai/mcp",
      "headers": {
        "x-api-key": "YOUR_API_KEY"
      }
    }
  }
}

Billing

Calls through the MCP server cost the same as the REST API: your account's humanize rate (from $0.14 per 1,000 words) and detection rate (from $0.02 per 1,000 words), paid from the plan's credits, with the same autopay and overage limit. Each result ends with a short note of the words billed and the cost. A refused call is never billed, and get_account_status is free.

See Pricing for how credits, autopay and the overage limit work.

Errors

A refused tool call comes back as a tool error the assistant relays as it is, naming the page that fixes it. Requests without valid credentials get an HTTP error instead:

401

Unauthorized

No credentials, an unknown or expired token, or an invalid API key. OAuth apps sign in again on their own.

405

Method Not Allowed

GET and DELETE: the server is stateless, so there is no session to stream or end.

Tool error	What it means
No active subscription	The account has no active plan. Subscribe on the pricing page.
Payment failed	API access is suspended after failed payments. Update the payment method in Settings.
Credits exhausted	The period's credits are used up and autopay is off. Turn on autopay in Settings.
Overage limit reached	Autopay hit the account's overage limit for the period. Raise it in Settings.
Rate limit	More than 300 requests a minute on one key, for humanizing or for detection.
Length	Humanize needs 20 to 5,000 words; detection needs 50 or more words and at most 15,000 characters.