Compatibility with HTTP middlewares

[sinedied]

I'm looking into implementing a MCP server on top of Azure Functions, and its implementation works as a classic Node.js HTTP middleware, requiring an IncomingMessage as the input request and OutgoingMessage for the response.

With the previous Functions v3 runtime model, we could use workarounds by creating adapters like this, but I'm wondering if we can have a similar approach with the v4 model?

In the new model v4 model we can't access/manipulate the response object directly as it must be returned in the function handler.

Any idea if/how we could have a way to create a compatibility layer/adapter to use regular HTTP middleware with the new v4 model?

cc @ejizba

[swapnil-nagar]

@sinedied Since MCP uses SSE as its protocol, request forwarding will work; however, function timeouts could be an issue. We're actively working on adding support for MCP and expect to have more details by mid-April.

[swapnil-nagar]

@sinedied We have just created an experimental tool called mcpTool, which you can find at https://github.com/Azure-Samples/remote-mcp-functions-typescript/. Please note that this tool is still in the experimental stage, and we will be improving and making it more reliable over the next few weeks.

Once you try this feature, feel free to provide suggestions or comments.