ChatGPT
Add the server URL as a custom MCP connector in ChatGPT and approve in the browser. The same connection works in the Codex app.
Connect with OAuth
In ChatGPT, open the MCPs tab and connect a custom MCP. Select Streamable HTTP, paste the server URL below, and complete the browser approval. No key to copy. Your client opens Unitpost in the browser — pick a workspace, approve the scopes, and you're connected. Tokens refresh automatically.
MCP server URL https://mcp.unitpost.com/mcp Custom MCP connectors may need developer mode, or a workspace admin on Business and Enterprise plans.
Verify
Start a chat with the unitpost connector enabled and ask ChatGPT to list your sending domains.
Send a test
Ask ChatGPT to send a test email from a verified domain. It asks you to confirm before sending; check the message in Unitpost Activity.
No browser on this machine? For headless setups, CI, SSH, or clients that can only paste a key, use the API-key setup instead.