diff --git a/homeassistant/components/zwave_js/api.py b/homeassistant/components/zwave_js/api.py
index 0339023b954f8..6eb54afb51a1e 100644
--- a/homeassistant/components/zwave_js/api.py
+++ b/homeassistant/components/zwave_js/api.py
@@ -13,8 +13,10 @@
 from zwave_js_server.const import (
     CommandClass,
     ExclusionStrategy,
+    InclusionState,
     InclusionStrategy,
     LogLevel,
+    NodeStatus,
     Protocols,
     ProvisioningEntryStatus,
     QRCodeVersion,
@@ -693,6 +695,30 @@ def forward_dsk(event: dict) -> None:
             )
         )
 
+    @callback
+    def forward_node_added(
+        node: Node, low_security: bool, low_security_reason: str | None
+    ) -> None:
+        interview_unsubs = [
+            node.on("interview started", forward_event),
+            node.on("interview completed", forward_event),
+            node.on("interview stage completed", forward_stage),
+            node.on("interview failed", forward_event),
+        ]
+        unsubs.extend(interview_unsubs)
+        node_details = {
+            "node_id": node.node_id,
+            "status": node.status,
+            "ready": node.ready,
+            "low_security": low_security,
+            "low_security_reason": low_security_reason,
+        }
+        connection.send_message(
+            websocket_api.event_message(
+                msg[ID], {"event": "node added", "node": node_details}
+            )
+        )
+
     @callback
     def forward_requested_grant(event: dict) -> None:
         connection.send_message(
@@ -727,25 +753,10 @@ def node_found(event: dict) -> None:
 
     @callback
     def node_added(event: dict) -> None:
-        node = event["node"]
-        interview_unsubs = [
-            node.on("interview started", forward_event),
-            node.on("interview completed", forward_event),
-            node.on("interview stage completed", forward_stage),
-            node.on("interview failed", forward_event),
-        ]
-        unsubs.extend(interview_unsubs)
-        node_details = {
-            "node_id": node.node_id,
-            "status": node.status,
-            "ready": node.ready,
-            "low_security": event["result"].get("lowSecurity", False),
-            "low_security_reason": event["result"].get("lowSecurityReason"),
-        }
-        connection.send_message(
-            websocket_api.event_message(
-                msg[ID], {"event": "node added", "node": node_details}
-            )
+        forward_node_added(
+            event["node"],
+            event["result"].get("lowSecurity", False),
+            event["result"].get("lowSecurityReason"),
         )
 
     @callback
@@ -777,25 +788,39 @@ def device_registered(device: dr.DeviceEntry) -> None:
     ]
     msg[DATA_UNSUBSCRIBE] = unsubs
 
-    try:
-        result = await controller.async_begin_inclusion(
-            INCLUSION_STRATEGY_NOT_SMART_START[inclusion_strategy.value],
-            force_security=force_security,
-            provisioning=provisioning,
-            dsk=dsk,
-        )
-    except ValueError as err:
-        connection.send_error(
+    if controller.inclusion_state == InclusionState.INCLUDING:
+        connection.send_result(
             msg[ID],
-            ERR_INVALID_FORMAT,
-            err.args[0],
+            True,  # Inclusion is already in progress
         )
-        return
+        # Check for nodes that have been added but not fully included
+        for node in controller.nodes.values():
+            if node.status != NodeStatus.DEAD and not node.ready:
+                forward_node_added(
+                    node,
+                    not node.is_secure,
+                    None,
+                )
+    else:
+        try:
+            result = await controller.async_begin_inclusion(
+                INCLUSION_STRATEGY_NOT_SMART_START[inclusion_strategy.value],
+                force_security=force_security,
+                provisioning=provisioning,
+                dsk=dsk,
+            )
+        except ValueError as err:
+            connection.send_error(
+                msg[ID],
+                ERR_INVALID_FORMAT,
+                err.args[0],
+            )
+            return
 
-    connection.send_result(
-        msg[ID],
-        result,
-    )
+        connection.send_result(
+            msg[ID],
+            result,
+        )
 
 
 @websocket_api.require_admin
diff --git a/tests/components/zwave_js/test_api.py b/tests/components/zwave_js/test_api.py
index 1d4ee7d4d86ca..05ffcee7f4eb9 100644
--- a/tests/components/zwave_js/test_api.py
+++ b/tests/components/zwave_js/test_api.py
@@ -5,7 +5,7 @@
 from io import BytesIO
 import json
 from typing import Any
-from unittest.mock import patch
+from unittest.mock import PropertyMock, patch
 
 import pytest
 from zwave_js_server.const import (
@@ -489,6 +489,7 @@ async def test_node_alerts(
 
 async def test_add_node(
     hass: HomeAssistant,
+    nortek_thermostat,
     nortek_thermostat_added_event,
     integration,
     client,
@@ -936,12 +937,46 @@ async def test_add_node(
         assert msg["error"]["code"] == "zwave_error"
         assert msg["error"]["message"] == "zwave_error: Z-Wave error 1 - error message"
 
+    # Test inclusion already in progress
+    client.async_send_command.reset_mock()
+    type(client.driver.controller).inclusion_state = PropertyMock(
+        return_value=InclusionState.INCLUDING
+    )
+
+    # Create a node that's not ready
+    node_data = deepcopy(nortek_thermostat.data)  # Copy to allow modification in tests.
+    node_data["ready"] = False
+    node_data["values"] = {}
+    node_data["endpoints"] = {}
+    node = Node(client, node_data)
+    client.driver.controller.nodes[node.node_id] = node
+
+    await ws_client.send_json(
+        {
+            ID: 11,
+            TYPE: "zwave_js/add_node",
+            ENTRY_ID: entry.entry_id,
+            INCLUSION_STRATEGY: InclusionStrategy.DEFAULT.value,
+        }
+    )
+
+    msg = await ws_client.receive_json()
+    assert msg["success"]
+
+    # Verify no command was sent since inclusion is already in progress
+    assert len(client.async_send_command.call_args_list) == 0
+
+    # Verify we got a node added event
+    msg = await ws_client.receive_json()
+    assert msg["event"]["event"] == "node added"
+    assert msg["event"]["node"]["node_id"] == node.node_id
+
     # Test sending command with not loaded entry fails
     await hass.config_entries.async_unload(entry.entry_id)
     await hass.async_block_till_done()
 
     await ws_client.send_json(
-        {ID: 11, TYPE: "zwave_js/add_node", ENTRY_ID: entry.entry_id}
+        {ID: 12, TYPE: "zwave_js/add_node", ENTRY_ID: entry.entry_id}
     )
     msg = await ws_client.receive_json()