Turn your API into a ChatGPT App
ChatGPT Apps and custom connectors are built on the Model Context Protocol. AnythingMCP generates that MCP backend from any API you already have — so ChatGPT can read and act on your business data without you writing a server.
Open source (AGPL-3.0) · self-hostable · credentials stay on your infrastructure
How it works
From API to ChatGPT in three steps
No Apps SDK boilerplate, no MCP server to write and host. The gateway is the backend.
Import your API
Upload an OpenAPI/Swagger spec, a Postman collection, a WSDL file or a cURL command — or point AnythingMCP at a database. 175+ pre-built adapters skip this step entirely.
Shape what ChatGPT sees
Rename tools, rewrite descriptions, hide parameters in the visual editor. You control exactly which operations ChatGPT can call.
Connect ChatGPT
Add your gateway URL as a connector in ChatGPT's settings, or use it as the tool layer of an Apps SDK app. OAuth 2.0 is supported out of the box.
Heads-up: a full ChatGPT App can also include custom UI components built with OpenAI's Apps SDK. AnythingMCP provides the MCP backend — the tools, auth, and data layer. For most business use cases, the backend is all you need.
Why teams pick AnythingMCP
One backend, every AI client
Build once, connect everywhere
The same connector works simultaneously in ChatGPT, Claude, Gemini, Copilot and Cursor — no per-client rework.
Credentials never leave your infra
API keys and OAuth tokens are stored AES-256-GCM encrypted in your Postgres — not in a third-party SaaS.
Every call is audited
Input, output, duration and status of every tool invocation land in an on-prem audit log, with role-based access on top.
Or start from 175+ ready-made connectors
DATEV, DHL, Personio, weclapp, Shopware, WooCommerce, Handelsregister, Sorare and many more — provide credentials and the tools are live in ChatGPT minutes later.
Browse the marketplaceFrequently asked questions
Can I build a ChatGPT App from my existing API?
Yes. ChatGPT Apps are built on MCP, and AnythingMCP generates the MCP backend from your existing API — REST, SOAP, GraphQL or a database. Add it as a connector in ChatGPT or use it as the tool layer of an Apps SDK app.
What's the difference between a ChatGPT App and a connector?
A connector exposes tools ChatGPT can call; an App adds custom UI components on top via OpenAI's Apps SDK. Both run on MCP. AnythingMCP provides the MCP backend that powers either.
Do I need the Apps SDK?
Not for tools-only use cases — add your AnythingMCP gateway as a ChatGPT connector and you're done. Reach for the Apps SDK only when you want custom interactive UI inside ChatGPT.
Do I need to write code?
No. Importing a spec, editing tools and connecting ChatGPT are all point-and-click. Code is only involved if you build custom Apps SDK UI on top.
Does the same connector work in Claude too?
Yes — it's the same MCP server. One gateway URL works in ChatGPT, Claude, Gemini, Copilot, Cursor and any other MCP-compatible client.
Put your data inside ChatGPT today
Free on the 7-day Cloud trial, free forever self-hosted.