defaultPinnedTools: include 'mcp' — omitting it unpins the Tools button itself (client seed sets PIN_MCP_=false)

librechat.yaml

@@ -84,8 +84,11 @@ modelSpecs:
 
 interface:
   customWelcome: "Welcome to your co-op AI."
-  # Tools pinned to the composer bar by default (members can unpin)
+  # Tools pinned to the composer bar by default (members can unpin).
+  # NOTE: 'mcp' MUST be listed or the Tools button itself gets unpinned by
+  # the client's default-pinning seed (hooks chunk gates PIN_MCP_ on this).
   defaultPinnedTools:
+    - mcp
     - web_search
   # Feature permissions (seeded for the USER role at startup;
   # ongoing edits belong in the LibreChat Admin Panel)