diff --git a/README.md b/README.md
index 383b71a..d8a0fd5 100644
--- a/README.md
+++ b/README.md
@@ -56,11 +56,27 @@ pip install -r requirements.txt
 
 The OpenRouter node provides a simple interface to interact with various LLMs through the OpenRouter API.
 
+### API Key Security
+
+> [!WARNING]
+> Entering your API key directly into the node's input field in ComfyUI will embed it in the **workflow metadata** of every image you save. This is a security risk if you share your images.
+
+To keep your API key secure, use one of the following methods:
+
+1.  **JSON Config File (Recommended)**:
+    - Create a file named `openrouter_api_key.json` in the node directory.
+    - Add your key like this: `{"api_key": "your_key_here"}`.
+    - Leave the **api_key** field blank in the ComfyUI interface.
+
+2.  **Environment Variable**:
+    - Set an environment variable named `LLM_KEY` on your system.
+    - The node will automatically pick it up if the UI field is empty.
+
 ### Inputs
 
 #### Required Inputs:
 
-- **api_key**: Your OpenRouter API key. You can get one from [OpenRouter](https://openrouter.ai/).
+- **api_key**: Your OpenRouter API key. Can be left blank if provided via `openrouter_api_key.json` or `LLM_KEY` environment variable.
 - **system_prompt**: The system prompt that sets the behavior of the LLM.
 - **user_message_box**: The user message to send to the LLM.
 - **model**: The model to use for generation. The node automatically fetches the list of available models from OpenRouter.
diff --git a/node.py b/node.py
index 75b4d56..c7f4a09 100644
--- a/node.py
+++ b/node.py
@@ -8,6 +8,7 @@ import torch
 import tiktoken
 from PIL import Image
 import hashlib # Added for hashing PDF bytes in IS_CHANGED
+import os
 from .chat_manager import ChatSessionManager
 
 # Define a placeholder type name for PDF data.
@@ -32,6 +33,35 @@ class OpenRouterNode:
     def __init__(self):
         self.chat_manager = ChatSessionManager()
 
+    def get_api_key(self, api_key_ui):
+        """
+        Resolves the API key from:
+        1. UI input field (if not empty)
+        2. Environment variable 'LLM_KEY'
+        3. config file 'openrouter_api_key.json' in node directory
+        """
+        if api_key_ui and api_key_ui.strip():
+            return api_key_ui.strip()
+
+        # Check environment variable
+        env_key = os.environ.get("LLM_KEY")
+        if env_key and env_key.strip():
+            return env_key.strip()
+
+        # Check JSON file
+        config_path = os.path.join(os.path.dirname(os.path.realpath(__file__)), "openrouter_api_key.json")
+        if os.path.exists(config_path):
+            try:
+                with open(config_path, 'r') as f:
+                    config = json.load(f)
+                    file_key = config.get("api_key")
+                    if file_key and file_key.strip():
+                        return file_key.strip()
+            except Exception as e:
+                print(f"Error reading openrouter_api_key.json: {e}")
+
+        return ""
+
     @classmethod
     def INPUT_TYPES(cls):
         """
@@ -136,6 +166,7 @@ class OpenRouterNode:
         Fetches the user's credits information from the OpenRouter API.
         Returns a formatted string with remaining credits.
         """
+        api_key = self.get_api_key(api_key)
         if not api_key:
              return "API Key not provided."
 
@@ -188,8 +219,12 @@ class OpenRouterNode:
         """
         # Create empty placeholder image
         placeholder_image = torch.zeros((1, 1, 1, 3), dtype=torch.float32)
+        
+        # Resolve API key
+        api_key = self.get_api_key(api_key)
+        
         if not api_key:
-             return ("Error: API Key not provided.", placeholder_image, "Stats N/A", "Credits N/A")
+             return ("Error: API Key not provided. Set LLM_KEY env var or use openrouter_api_key.json", placeholder_image, "Stats N/A", "Credits N/A")
 
         url = "https://openrouter.ai/api/v1/chat/completions"
         headers = {
@@ -643,6 +678,8 @@ class OpenRouterNode:
 
         # Combine all relevant inputs into a tuple for comparison
         # Use primitive types where possible for reliable hashing/comparison
+        # Note: We don't hash the resolved API key from file/env to avoid re-running 
+        # if only the hidden key changes (which is rare), but we still pass the UI value.
         return (api_key, system_prompt, user_message_box, model,
                 web_search, cheapest, fastest, temp_float, pdf_engine, chat_mode,
                 aspect_ratio, image_resolution, seed, tuple(image_hashes), pdf_hash, user_message_input)
diff --git a/openrouter_api_key.json.example b/openrouter_api_key.json.example
new file mode 100644
index 0000000..3124938
--- /dev/null
+++ b/openrouter_api_key.json.example
@@ -0,0 +1,3 @@
+{
+    "api_key": "your_openrouter_api_key_here"
+}