diff --git a/README.md b/README.md
index 2d88a19..e9cb713 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,20 @@
 # Cauldron Cloud — MCP Server
 
+> ## ⚠️ DEPRECATED — do not use for new work
+>
+> This standalone **stdio** client was a test and is **dismissed**. It is no
+> longer maintained and may lag behind the API.
+>
+> Use the built-in **HTTP MCP** instead — no install, just a URL with your API key:
+>
+> ```
+> https://cauldron.cloud/mcp/<YOUR_API_KEY>
+> ```
+>
+> It is implemented server-side (`src/Controllers/McpServerController.php` in the
+> main `cauldron` repo) and is the only transport that receives new tools/filters.
+> Add it as a custom connector in Claude (Settings → Connectors → Add) with that URL.
+
 Connects Claude Desktop (or any MCP client) to the Cauldron M&A portal.
 
 ## Quick setup — 3 commands
diff --git a/server.py b/server.py
index 910be5c..8758755 100644
--- a/server.py
+++ b/server.py
@@ -1,6 +1,12 @@
 #!/usr/bin/env python3
 """
 Cauldron Cloud — MCP Server
+
+DEPRECATED (dismissed): this standalone stdio client was a test and is no longer
+maintained. Development continues only on the HTTP MCP transport, served at
+https://cauldron.cloud/mcp/<API_KEY> (src/Controllers/McpServerController.php in
+the main cauldron repo). Kept here for reference only.
+
 Connects Claude Desktop (or any MCP client) to the Cauldron portal REST API.
 
 Setup: