What is the Neural Link?

The Neural Link is a bi-directional bridge that connects AI agents directly to the Neo.mjs runtime. It lets agents inspect the Scene Graph, component state, event listeners, computed styles, and DOM rectangles, and mutate the running application in real time.

Why is Neo.mjs called an Application Engine instead of a framework?

Neo.mjs maintains persistent application objects in a worker-backed Scene Graph instead of compiling application state away into ephemeral DOM nodes. That architecture enables multi-window orchestration, runtime permutation, and deep AI introspection.

What is Context Engineering?

Context Engineering shapes the information and tool environment around AI agents. Neo.mjs implements it through Knowledge Base, Memory Core, GitHub Workflow, and Neural Link MCP servers for frontier harnesses, plus a File System MCP server for internal Neo.ai.Agent local loops.

What is the Neo.mjs Agent OS?

The Neo.mjs Agent OS is the repository Brain: source code and services for Memory Core, Knowledge Base, Active Hybrid GraphRAG, DreamService, Golden Path synthesis, A2A coordination, and Neural Link tooling.

Frontmatter

id	9533
title	Migrate MCP servers from SSEServerTransport to StreamableHTTPServerTransport
state	Closed
labels	enhancementai
assignees	tobiu
createdAt	Mar 23, 2026, 5:03 PM
updatedAt	Mar 23, 2026, 5:56 PM
githubUrl	https://github.com/neomjs/neo/issues/9533
author	tobiu
commentsCount	2
parentIssue	null
subIssues	[]
subIssuesCompleted	0
subIssuesTotal	0
contentTrust
projected
quarantined	0
signals	[]
blockedBy	[]
blocking	[]
closedAt	Mar 23, 2026, 5:56 PM

Migrate MCP servers from SSEServerTransport to StreamableHTTPServerTransport

Closed v12.1.0/archive-v12-1-0-chunk-2 enhancementai

tobiu commented on Mar 23, 2026, 5:03 PM

Description

During the implementation of the SSE transport for the MCP servers (knowledge-base and memory-core), we noticed a deprecation warning indicating that SSEServerTransport is deprecated in favor of StreamableHTTPServerTransport (protocol version 2025-11-25).

The @modelcontextprotocol/sdk now recommends using StreamableHTTPServerTransport along with @hono/node-server (which the SDK wraps natively via StreamableHTTPServerTransport) to handle the SSE transport in Node.js HTTP servers.

Investigation Findings

The SDK provides a createMcpExpressApp wrapper in @modelcontextprotocol/sdk/server/express.js.
The new StreamableHTTPServerTransport handles GET, POST, and DELETE on a single endpoint (e.g., /mcp), rather than splitting GET for SSE streams and POST for messages into separate endpoints.
It requires maintaining a mapping of sessions (using req.headers['mcp-session-id']) to reuse the transport instance per session.
Our authMiddleware will still work, but we will need to update our dynamic SSE loader in Server.mjs to implement this stateful routing architecture correctly.

Tasks

Investigate and map out the exact routing logic needed to replace SSEServerTransport with StreamableHTTPServerTransport.
Refactor the dynamic Express server initialization in knowledge-base and memory-core MCP servers.
Ensure the authentication middleware hook remains functional with the new approach.

tobiu Mar 23, 2026, 5:49 PM

Input from Gemini 3.1 Pro:

✦ ✦ I have completed the migration.

I successfully refactored the dynamic SSE transport logic in both knowledge-base/Server.mjs and memory-core/Server.mjs to use StreamableHTTPServerTransport from the new @modelcontextprotocol/sdk.

The endpoints have been unified under /mcp, utilizing createMcpExpressApp to ensure DNS rebinding protection. I also implemented stateful session management utilizing sessionIdGenerator to map distinct client sessions seamlessly.

Changes have been successfully committed and pushed to dev. I'll close this ticket now.

tobiu Mar 23, 2026, 5:55 PM

Input from Gemini 3.1 Pro:

✦ ✦ I agree, that's a good optimization. I've updated both servers to dynamically import StdioServerTransport only when falling back to stdio. The changes have been pushed, and I will now close this issue.

2026-05-22T02:41:25Z @neo-gpt cross-referenced by #11744
2026-07-14T22:13:21Z @neo-gpt cross-referenced by #15188
2026-07-16T05:33:05Z @neo-opus-vega cross-referenced by PR #15191