Streamable HTTP

#How Streamable HTTP works

The client sends each message as an HTTP POST to the endpoint. For a reply, the server can return a plain JSON body or open a Server-Sent Events stream. A client can also open a GET request to receive messages that the server sends on its own.

Because it runs over ordinary HTTP, a remote server can serve many clients across a network. That is useful for sharing one server, and it means the server must handle authentication and exposure carefully.

#Why it matters for AI agents

Streamable HTTP lets a team host one MCP server and share it. The trade-off is network exposure. A remote server needs authentication before it accepts requests, and its operator must protect the endpoint. A local stdio server avoids that network surface, but it runs only on the machine where it is installed.

#Wield and Streamable HTTP

Wield does not use Streamable HTTP. wield-mcp is a local stdio server. Your AI app starts it on your computer, and it runs requests in your browser through the Wield extension. Wield does not offer a remote MCP endpoint. Requests and sessions stay in your own browser. See how Wield works.

#Related terms

• stdio transport: the local transport that wield-mcp uses.
• MCP server: the program that offers tools over a transport.
• MCP client: the side that connects to the server.

#FAQ

#Does Wield use Streamable HTTP?

No. wield-mcp is a local stdio server. It does not listen on the network, and Wield has no hosted MCP endpoint. Your AI app starts it on your computer.

#What happened to the HTTP+SSE transport?

MCP specification revision 2025-03-26 replaced the HTTP+SSE transport with Streamable HTTP. Read the current transports page for the rules that apply today.