About mcp-transport-prototype
mcp-transport-prototype is a prototype for learning to build custom MCP servers with stdio and SSE transports. It is aimed at developers exploring process-based and HTTP-based communication patterns.
Key features
- 01Custom MCP server prototype
- 02stdio transport
- 03SSE transport
- 04Client test script
Use cases
- 01Learning MCP transport patterns
- 02Testing an MCP server over SSE
MCP support
The project demonstrates an MCP server accessible through stdio and SSE. Its included mcp_client.py script tests the server in SSE mode.
Configuration
Local server config is the same for every client. Copy it into your client’s MCP config file.
We haven’t collected a package or remote endpoint for this server. Follow the instructions in the project README.
Tools
Local servers expose tools only once running on your machine, and the maintainer has not provided a tool list.
Details
From the project READMEmcp-transport-prototype
A prototype implementation to understand building custom MCP server that is accessible over stdio and SSE transport. The goal here is to understand SSE and stdio transports.
SSE Transport
Server-Sent Events (SSE) is a simple, efficient way to push real-time updates from the server to the client over HTTP.
- Unlike WebSockets, SSE is one-way: the server can stream data to the client, but not vice versa.
- It works over standard HTTP and is well-suited for scenarios like live updates, notifications, or streaming responses.
Unlike stdio, SSE runs the MCP server as a separate HTTP service. This makes it well-suited for use cases like web dashboards or browser-based apps that need to receive streamed updates from the server over the network.
Stdio Transport
Stdio (short for standard input/output) is a traditional way for programs to communicate by reading from and writing to the terminal or connected processes.
stdin(standard input): receives input data — usually from the keyboard, a file, or another program.stdout(standard output): sends output data — usually printed on the terminal or piped to another program.
Compared to SSE, stdio-based MCP servers feel more like in-process tools. They're ideal when you're launching the MCP server as a subprocess, such as from a command-line tool, an LLM agent, or a background script that needs to send and receive structured data efficiently without using a network.
See in Action
mcp_client.py is a quick script to test MCP server in SSE mode.
# Run in Terminal 1
uv run main.py
# Run in Terminal 2
uv run mcp_client.py
Comments
New to MCP?
From what the protocol is to installing your first server, these answers cover most first questions.
An open protocol that defines how AI applications connect to external tools and data in a uniform way. Clients talk to the model; MCP servers provide tools, resources and prompt templates. They exchange standard messages, so one server can be reused by many clients.