OnlyX Developers

OnlyX is the AI chatting and CRM platform for OnlyFans agencies. Its AI chatter, Hugo, answers fans in each creator’s voice, sells her content, and hands conversations to your team when a human should step in. The OnlyX API and the OnlyX MCP server give you the same control you have in app.onlyx.ai, from your own code or from an AI assistant such as Claude, ChatGPT or Cursor.

Quickstart

Create a key and make your first five calls in about five minutes.

Connect your AI assistant

Add OnlyX to Claude, ChatGPT, Cursor or VS Code in one click. No code.

What you can do

Add a creator

Add a creator and send her a connect link. She signs in to OnlyFans herself, including face verification.

Read and send messages

Read any chat, send text, vault media and paid messages, and track delivery.

Handle hand-offs

See the chats the AI handed to your team, and resolve them.

Work with fans

Find whales, lapsing subscribers and recent buyers; add notes and custom names.

Use vault media

Browse each creator’s vault and use media ids in messages and content levels.

Pull stats

Today’s numbers, revenue by day and by seller, audience, and the transaction ledger.

Set up the AI persona

Tell the AI who the creator is, how she writes, and what she will never do.

Build the AI content ladder

Organize vault media into priced levels the AI offers in order.

Tune AI settings

Follow-ups, review mode, and the OnlyFans welcome message.

Track promotion links

List tracking links with clicks, subscribers, cost and ROI, and create new ones.

Use OnlyX from Claude

Ready-made recipes: daily briefing, safe replies to unread fans, onboarding, weekly report.

Handle errors and limits

Every error code, what to retry, rate limits, pagination and idempotency.

The basics


Base URL	`https://api.onlyx.ai/v1`
Authentication	`Authorization: Bearer onx_sk_...` (an API key) or an OAuth access token. See Authentication.
Format	JSON over HTTPS, UTF-8, `camelCase` field names
Money	Integer US cents in fields that end in `Cents` (`1999` is $19.99)
Time	ISO-8601 UTC timestamps, for example `2026-09-26T14:05:00.000Z`. Reports use your workspace’s timezone for days.
Lists	`{"data": [...], "hasMore": true, "nextCursor": "..."}`. See Pagination.
Errors	`{"error": {"code", "message", "requestId"}}`. See Errors.
MCP server	`https://mcp.onlyx.ai/mcp`. See MCP overview.
OpenAPI schema	`https://api.onlyx.ai/v1/openapi.json` (no key needed)

Keys belong to your workspace, not to a person. Only workspace owners and admins can create them, in Settings → API & MCP at app.onlyx.ai.

A 60-second example

List your creators, then the unread conversations of the first one.

export ONLYX_API_KEY="onx_sk_..."   # from Settings → API & MCP

curl https://api.onlyx.ai/v1/creators \
  -H "Authorization: Bearer $ONLYX_API_KEY"

curl "https://api.onlyx.ai/v1/conversations?creatorId=cre_5f2d9a1c7b3e4f60a2d1&unread=true&limit=10" \
  -H "Authorization: Bearer $ONLYX_API_KEY"

import os
import requests

API = "https://api.onlyx.ai/v1"
HEADERS = {"Authorization": f"Bearer {os.environ['ONLYX_API_KEY']}"}

creators = requests.get(f"{API}/creators", headers=HEADERS, timeout=30).json()["data"]
first = creators[0]
print("Creator:", first["displayName"], first["connection"]["status"])

chats = requests.get(
    f"{API}/conversations",
    headers=HEADERS,
    params={"creatorId": first["id"], "unread": "true", "limit": 10},
    timeout=30,
).json()["data"]
for chat in chats:
    last = chat["lastMessage"]["text"] if chat["lastMessage"] else ""
    print(chat["fan"]["displayName"], chat["status"], chat["unreadCount"], last[:60])

const API = "https://api.onlyx.ai/v1";
const headers = { Authorization: `Bearer ${process.env.ONLYX_API_KEY}` };

const creators = (await (await fetch(`${API}/creators`, { headers })).json()).data;
const first = creators[0];
console.log("Creator:", first.displayName, first.connection.status);

const params = new URLSearchParams({ creatorId: first.id, unread: "true", limit: "10" });
const chats = (await (await fetch(`${API}/conversations?${params}`, { headers })).json()).data;
for (const chat of chats) {
  console.log(chat.fan.displayName, chat.status, chat.unreadCount, chat.lastMessage?.text?.slice(0, 60) ?? "");
}

Response (GET /v1/conversations, shortened)

{
  "data": [
    {
      "id": "cnv_9f2c41d7a8b35e06c1f4",
      "creatorId": "cre_5f2d9a1c7b3e4f60a2d1",
      "fan": {
        "id": "fan_3b7e9d2a1c5f48e06b92",
        "displayName": "Jake",
        "username": "jake_91",
        "avatarUrl": "https://..."
      },
      "status": "ai",
      "unreadCount": 2,
      "lastMessage": { "text": "are you online rn?", "direction": "in", "at": "2026-09-26T13:58:12.000Z" },
      "lastMessageAt": "2026-09-26T13:58:12.000Z",
      "takenOverUntil": null,
      "totalSpentCents": 48500
    }
  ],
  "hasMore": false,
  "nextCursor": null
}

Two ways to build

REST API

For your own dashboards, bots, CRMs and automations. Scoped API keys, idempotent writes, predictable rate limits.

MCP server

For AI assistants. The same capabilities as 60 tools, with OAuth sign-in and confirmation before anything reaches a fan.

Ground rules

Anything that reaches a fan is a real message to a real person, usually with real money attached. Sends, releasing a chat back to the AI, turning the AI on for a chat, and resolving a hand-off can all produce a message. Build confirmation into your tools, and see Read and send messages.
Never resend a message whose delivery is unconfirmed. The fan almost always received it.
The API never takes OnlyFans passwords or verification codes. Creators sign in themselves with the OnlyX Login app. See Add a creator.
Send an Idempotency-Key with every write that sends, creates, or reaches fans, and reuse it when you retry, so a retry can never act twice. It is required for sending messages, adding creators and creating tracking links. See Idempotency.

Need help or found a security issue? Email security@onlyx.ai for security reports; see Security.

Get started

Guides

Reference topics

Quickstart

Connect your AI assistant

What you can do

Add a creator

Read and send messages

Handle hand-offs

Work with fans

Use vault media

Pull stats

Set up the AI persona

Build the AI content ladder

Tune AI settings

Track promotion links

Use OnlyX from Claude

Handle errors and limits

The basics

A 60-second example

Two ways to build

REST API

MCP server

Ground rules

Quickstart

Connect your AI assistant

​What you can do

Add a creator

Read and send messages

Handle hand-offs

Work with fans

Use vault media

Pull stats

Set up the AI persona

Build the AI content ladder

Tune AI settings

Track promotion links

Use OnlyX from Claude

Handle errors and limits

​The basics

​A 60-second example

​Two ways to build

REST API

MCP server

​Ground rules

What you can do

The basics

A 60-second example

Two ways to build

Ground rules