GPT

0nGPT

ChatGPT App Integration for 0nMCP

Use 1,589 0nMCP tools directly inside ChatGPT conversations. Send invoices, manage contacts, create workflows, query databases — all through natural language in ChatGPT.

What You Get

Full MCP Tool Access

All 1,589 tools available in ChatGPT — CRM, Stripe, Slack, GitHub, LinkedIn, and 102 more services.

OAuth 2.1 + PKCE

Secure authentication with proof key for code exchange. Your credentials stay protected.

Branded Widget

0nMCP-branded iframe widget inside ChatGPT with tool status, execution history, and connection management.

JWT Verification

Every MCP tool call verifies the bearer JWT via JWKS. No token, no execution.

How It Works

// Architecture
ChatGPT → OAuth 2.1 (PKCE) → 0nMCP Auth Server
                                    ↓
              JWT issued → Bearer token in every tool call
                                    ↓
              0nMCP MCP Server → JWKS verification
                                    ↓
              Tool execution → 102 services
                                    ↓
              Result → ChatGPT conversation

Included Files

apps-sdk/server/index.tsMCP server entry — tools + ext-apps UI registration

apps-sdk/server/auth.tsBearer JWT verification via JWKS

apps-sdk/web/widget.htmlBranded iframe widget for ChatGPT

app/api/.well-known/*OAuth discovery endpoint

app/api/chatgpt/oauth.route.tsOAuth register / authorize / token routes

supabase/migrations/*4 OAuth tables (clients, codes, tokens, requests)

chatgpt-app.0nVault config file for the integration

Get 0nGPT

Request access to deploy 0nGPT in your ChatGPT environment.

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