diff --git a/README.md b/README.md
index abdcb1e..3074988 100644
--- a/README.md
+++ b/README.md
@@ -147,6 +147,7 @@ This repository offers various extension nodes for ComfyUI. Nodes here have diff
     * When `key_opt` is empty, the `ckpt_name` is set as the cache key. The cache key output can be used for deletion purposes with Remove Back End.
     * This node resolves the issue of reloading checkpoints during workflow switching.
   * `Stable Cascade Checkpoint Loader (Inspire)`: This node provides a feature that allows you to load the `stage_b` and `stage_c` checkpoints of Stable Cascade at once, and it also provides a backend caching feature, optionally.
+  * `Is Cached (Inspire)`: Returns whether the cache exists.
 
 ### Conditioning - Nodes for conditionings
   * `Concat Conditionings with Multiplier (Inspire)`: Concatenating an arbitrary number of Conditionings while applying a multiplier for each Conditioning. The multiplier depends on `comfy_PoP`, so [comfy_PoP](https://github.com/picturesonpictures/comfy_PoP) must be installed.
diff --git a/__init__.py b/__init__.py
index 023a96e..3e989e7 100644
--- a/__init__.py
+++ b/__init__.py
@@ -7,7 +7,7 @@
 
 import importlib
 
-version_code = [1, 8]
+version_code = [1, 9]
 version_str = f"V{version_code[0]}.{version_code[1]}" + (f'.{version_code[2]}' if len(version_code) > 2 else '')
 print(f"### Loading: ComfyUI-Inspire-Pack ({version_str})")
 
diff --git a/inspire/backend_support.py b/inspire/backend_support.py
index edebb2f..9b4eb28 100644
--- a/inspire/backend_support.py
+++ b/inspire/backend_support.py
@@ -1,5 +1,6 @@
 import json
 import os
+from .libs import common
 
 import folder_paths
 import nodes
@@ -478,6 +479,74 @@ def doit(self, stage_b, key_opt_b, stage_c, key_opt_c, cache_mode):
         return b_model, b_vae, c_model, c_vae, clip_vision, clip, key_b, key_c
 
 
+class IsCached:
+    @classmethod
+    def INPUT_TYPES(s):
+        return {
+            "required": {
+                "key": ("STRING", {"multiline": False}),
+            },
+            "hidden": {
+                "unique_id": "UNIQUE_ID"
+            }
+        }
+
+    RETURN_TYPES = ("BOOLEAN", )
+    FUNCTION = "doit"
+
+    CATEGORY = "InspirePack/Backend"
+
+    @staticmethod
+    def IS_CHANGED(key, unique_id):
+        return common.is_changed(unique_id, key in cache)
+
+    def doit(self, key, unique_id):
+        return (key in cache,)
+
+
+# WIP: not properly working, yet
+class CacheBridge:
+    @classmethod
+    def INPUT_TYPES(s):
+        return {
+            "required": {
+                "value": (any_typ,),
+                "mode": ("BOOLEAN", {"default": True, "label_off": "cached", "label_on": "passthrough"}),
+            },
+            "hidden": {
+                "unique_id": "UNIQUE_ID"
+            }
+        }
+
+    RETURN_TYPES = (any_typ, )
+    RETURN_NAMES = ("value",)
+
+    FUNCTION = "doit"
+
+    CATEGORY = "InspirePack/Backend"
+
+    @staticmethod
+    def IS_CHANGED(value, mode, unique_id):
+        if not mode and unique_id in common.changed_cache:
+            return common.not_changed_value(unique_id)
+        else:
+            return common.changed_value(unique_id)
+
+    def doit(self, value, mode, unique_id):
+        if not mode:
+            # cache mode
+            if unique_id not in common.changed_cache:
+                common.changed_cache[unique_id] = value
+                common.changed_count_cache[unique_id] = 0
+
+            return (common.changed_cache[unique_id],)
+        else:
+            common.changed_cache[unique_id] = value
+            common.changed_count_cache[unique_id] = 0
+
+            return (common.changed_cache[unique_id],)
+
+
 NODE_CLASS_MAPPINGS = {
     "CacheBackendData //Inspire": CacheBackendData,
     "CacheBackendDataNumberKey //Inspire": CacheBackendDataNumberKey,
@@ -489,7 +558,9 @@ def doit(self, stage_b, key_opt_b, stage_c, key_opt_c, cache_mode):
     "RemoveBackendDataNumberKey //Inspire": RemoveBackendDataNumberKey,
     "ShowCachedInfo //Inspire": ShowCachedInfo,
     "CheckpointLoaderSimpleShared //Inspire": CheckpointLoaderSimpleShared,
-    "StableCascade_CheckpointLoader //Inspire": StableCascade_CheckpointLoader
+    "StableCascade_CheckpointLoader //Inspire": StableCascade_CheckpointLoader,
+    "IsCached //Inspire": IsCached,
+    # "CacheBridge //Inspire": CacheBridge,
 }
 
 NODE_DISPLAY_NAME_MAPPINGS = {
@@ -503,5 +574,7 @@ def doit(self, stage_b, key_opt_b, stage_c, key_opt_c, cache_mode):
     "RemoveBackendDataNumberKey //Inspire": "Remove Backend Data [NumberKey] (Inspire)",
     "ShowCachedInfo //Inspire": "Show Cached Info (Inspire)",
     "CheckpointLoaderSimpleShared //Inspire": "Shared Checkpoint Loader (Inspire)",
-    "StableCascade_CheckpointLoader //Inspire": "Stable Cascade Checkpoint Loader (Inspire)"
+    "StableCascade_CheckpointLoader //Inspire": "Stable Cascade Checkpoint Loader (Inspire)",
+    "IsCached //Inspire": "Is Cached (Inspire)",
+    # "CacheBridge //Inspire": "Cache Bridge (Inspire)"
 }
diff --git a/inspire/inspire_server.py b/inspire/inspire_server.py
index 241b8f4..01b8a88 100644
--- a/inspire/inspire_server.py
+++ b/inspire/inspire_server.py
@@ -6,6 +6,7 @@
 from . import prompt_support
 from aiohttp import web
 from . import backend_support
+from .libs import common
 
 
 max_seed = 2**32 - 1
@@ -354,6 +355,21 @@ def force_reset_useless_params(json_data):
     return json_data
 
 
+def clear_unused_node_changed_cache(json_data):
+    prompt = json_data['prompt']
+
+    unused = []
+    for x in common.changed_cache.keys():
+        if x not in prompt:
+            unused.append(x)
+
+    for x in unused:
+        del common.changed_cache[x]
+        del common.changed_count_cache[x]
+
+    return json_data
+
+
 def onprompt(json_data):
     prompt_support.list_counter_map = {}
 
@@ -367,6 +383,7 @@ def onprompt(json_data):
     populate_wildcards(json_data)
 
     force_reset_useless_params(json_data)
+    clear_unused_node_changed_cache(json_data)
 
     return json_data
 
diff --git a/inspire/libs/common.py b/inspire/libs/common.py
index 7a4b296..84cba0e 100644
--- a/inspire/libs/common.py
+++ b/inspire/libs/common.py
@@ -12,3 +12,30 @@ def impact_sampling(*args, **kwargs):
         raise Exception(f"[ERROR] You need to install 'ComfyUI-Impact-Pack'")
 
     return nodes.NODE_CLASS_MAPPINGS['RegionalSampler'].separated_sample(*args, **kwargs)
+
+
+changed_count_cache = {}
+changed_cache = {}
+
+
+def changed_value(uid):
+    v = changed_count_cache.get(uid, 0)
+    changed_count_cache[uid] = v + 1
+    return v + 1
+
+
+def not_changed_value(uid):
+    return changed_count_cache.get(uid, 0)
+
+
+def is_changed(uid, value):
+    if uid not in changed_cache or changed_cache[uid] != value:
+        res = changed_value(uid)
+    else:
+        res = not_changed_value(uid)
+
+    changed_cache[uid] = value
+
+    print(f"keys: {changed_cache.keys()}")
+
+    return res
diff --git a/pyproject.toml b/pyproject.toml
index 020a40f..37b3042 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,7 @@
 [project]
 name = "comfyui-inspire-pack"
 description = "This extension provides various nodes to support Lora Block Weight, Regional Nodes, Backend Cache, Prompt Utils, List Utils, Noise(Seed) Utils, ... and the Impact Pack."
-version = "1.8"
+version = "1.9"
 license = { file = "LICENSE" }
 dependencies = ["matplotlib", "cachetools"]