ChatGPT + VIA
ChatGPT and Codex connect to remote MCP servers over Streamable HTTP. The one thing that trips people up: VIA needs no login and no token, so leave any bearer-token field blank. Available on Plus, Pro, Business, Enterprise, and Education accounts.
Enable Developer Mode
On chatgpt.com, open Settings → Connectors (in some versions Apps & Connectors → Advanced settings) and turn Developer mode on. That is what lets you add a custom MCP server. (Workspace admins may need to allow it under Settings → Permissions & Roles → Connected Data.)
Add the custom MCP server
Click Create or Add custom connector. In the dialog:
Type / Transport: Streamable HTTP. Name: VIA. URL: https://www.getvia.xyz/mcp. Authentication: None, leave the Bearer token and Headers fields empty.
Confirm and save
Check the risk acknowledgement box, click Create, then open the connector's details page to confirm its tools are listed (find_seller, get_product, buy_product, and others).
Use it in a chat
In a new conversation, click the + in the composer, pick VIA, and ask it anything. ChatGPT will prompt for confirmation on the first tool call.
https://www.getvia.xyz/mcp as the URL, and leave the Bearer token and Headers fields blank. No MCP_BEARER_TOKEN is needed.