devspace-memory-bridge

A non-invasive MCP bridge that makes DevSpace search tools memory-aware.

devspace-memory-bridge sits in front of a normal DevSpace server and augments selected search/list tool responses with structural context from codebase-memory-mcp. The model still calls ordinary DevSpace-style tools such as grep, glob, and ls; the bridge enriches the response locally before it reaches the client.

ChatGPT / MCP client
  -> devspace-memory-bridge
    -> upstream DevSpace
    -> codebase-memory-mcp CLI

Why this exists

Some coding agents support hooks that can automatically inject codebase context when the agent searches files. Other MCP clients do not expose that kind of hook surface. This project explores a practical middle ground: intercept only the DevSpace search/list tools at the local boundary, call the real DevSpace tool, call codebase-memory-mcp, and return one combined tool result.

The goal is not to replace DevSpace or codebase-memory-mcp. The goal is to connect them without patching either upstream project.

What it does

Implemented:

• Records workspaceId -> root from open_workspace results.
• Passes unknown and non-memory tools through unchanged.
• Augments grep / grep_files with search_graph context.
• Augments glob / find_files with search_graph context.
• Augments ls / list_directory with lightweight architecture context.
• Transforms JSON-RPC JSON responses.
• Transforms request-scoped MCP SSE responses from POST /mcp.
• Streams standalone GET /mcp SSE responses through unchanged.
• Fails open by default: if memory lookup fails, the original DevSpace result is returned.

Intentionally not implemented yet:

• bash command interception.
• read, edit, or write augmentation.
• A full DevSpace replacement.
• A general-purpose MCP middleware framework.

Not yet validated end-to-end:

• ChatGPT Apps OAuth/resource-server registration through the bridge.
• Long-lived production deployment behind a public HTTPS tunnel.

Tool behavior

The bridge treats upstream DevSpace as the source of truth. A normal request flow is:

1. Client calls grep(pattern="TurnController")
2. Bridge forwards the call to upstream DevSpace
3. DevSpace returns normal grep results
4. Bridge extracts symbol hints from the search pattern
5. Bridge calls codebase-memory-mcp search_graph
6. Bridge appends "Codebase Memory Context" to the tool result
7. Client receives what still looks like a grep result

If step 5 fails, step 6 is skipped and the original DevSpace response is returned.

Requirements

• Node.js 22 or newer.
• A running DevSpace server.
• codebase-memory-mcp available as a CLI command, or a compatible wrapper command.
• Upstream DevSpace should run with dedicated search/list tools enabled:

DEVSPACE_TOOL_MODE=full node /path/to/devspace/dist/cli.js serve

Quick start

Start upstream DevSpace:

DEVSPACE_TOOL_MODE=full node /home/heppo/DEV/devspace/dist/cli.js serve

Start the bridge:

cd /home/heppo/DEV/devspace-memory-bridge

DEVSPACE_UPSTREAM_URL=http://127.0.0.1:7676 \
DEVSPACE_MEMORY_BRIDGE_PORT=7777 \
DEVSPACE_MEMORY_COMMAND=codebase-memory-mcp \
node src/index.js

Point the MCP client at the bridge instead of upstream DevSpace.

Configuration

Variable	Default	Purpose
DEVSPACE_UPSTREAM_URL	http://127.0.0.1:7676	Real DevSpace server URL.
DEVSPACE_MEMORY_BRIDGE_HOST	127.0.0.1	Bridge bind host.
DEVSPACE_MEMORY_BRIDGE_PORT	7777	Bridge bind port.
DEVSPACE_MEMORY_COMMAND	codebase-memory-mcp	CLI command used for memory lookups.
DEVSPACE_MEMORY_AUGMENT_TOOLS	grep,glob,ls	Tools to augment.
DEVSPACE_MEMORY_FAIL_OPEN	true	Return normal DevSpace results if memory lookup fails.
DEVSPACE_MEMORY_MAX_CONTEXT_CHARS	6000	Max appended memory context length.

Tests

npm test
npm run check

Current test coverage focuses on the bridge logic rather than a live ChatGPT/DevSpace OAuth round trip:

• memory context formatting
• symbol hint extraction
• JSON-RPC tool response transformation
• fail-open behavior
• non-memory tool pass-through
• request-scoped SSE transformation

Security model

This bridge sits in front of a local coding workspace. Treat it as sensitive infrastructure.

• Bind to localhost by default.
• Put authentication and HTTPS at the outer boundary if exposed remotely.
• Do not expose it directly to the public internet.
• Keep fail-open enabled unless you explicitly want memory failures to break tool calls.
• Review upstream DevSpace permissions and allowed roots before use.

Design rules

• Do not patch DevSpace upstream.
• Do not patch codebase-memory-mcp upstream.
• Treat DevSpace as the source of truth for filesystem operations.
• Only append memory context after the upstream DevSpace call succeeds.
• Unknown tools must pass through unchanged.
• Memory failures must not break local coding tools.

Status

Prototype. The core transformation behavior is implemented and tested, but production ChatGPT Apps registration through the bridge still needs end-to-end validation.

License

MIT