diff --git a/README.md b/README.md
index 7392070..3693da0 100644
--- a/README.md
+++ b/README.md
@@ -43,7 +43,7 @@ Simply run `llmpeg "with your instructions in quotes"`. See examples below for m
 
 For more detailed information, run `llmpeg -h`:
 ```
-usage: llmpeg [-h] [--backend {openai}] [--openai_model OPENAI_MODEL] instructions
+Usage: main.py [-h] [-k KEY] [-b {openai}] [-m OPENAI_MODEL] instructions
 
 Convert your instructions into an ffmpeg command.
 
@@ -52,10 +52,11 @@ positional arguments:
 
 optional arguments:
   -h, --help            show this help message and exit
-  --backend {openai}    The backend LLM API provider to use. Defaults to 'openai'.
-  --openai_model OPENAI_MODEL
+  -k KEY, --key KEY     OpenAI API Key to use. Defaults to 'OPENAI_API_KEY' environment variable.
+  -b {openai}, --backend {openai}
+                        The backend LLM API provider to use. Defaults to 'openai'.
+  -m OPENAI_MODEL, --openai_model OPENAI_MODEL
                         The OpenAI LLM Model that you would like to use.
-
 ```
 ### OpenAI
 By default, `openai_model` is set to `gpt-3.5-turbo-0125`, which as of today, as the strongest model that can be used with a free developer account with $5 of free credit. If you have a developer account and are willing to pay for credits, you can change this to one of the `gpt-4` models for better performance and more accurate command generation.
diff --git a/llmpeg/main.py b/llmpeg/main.py
index 4484162..4a61b5e 100755
--- a/llmpeg/main.py
+++ b/llmpeg/main.py
@@ -278,8 +278,20 @@ def main():
         type=str,
         help="A string containing instructions about the desired ffmpeg use",
     )
+
+    parser.add_argument(
+        "-k",
+        "--key",
+        dest="key",
+        type=str,
+        default=os.environ.get("OPENAI_API_KEY", None),
+        help="OpenAI API Key to use. Defaults to 'OPENAI_API_KEY' environment variable.",
+    )
+
     parser.add_argument(
+        "-b",
         "--backend",
+        dest="backend",
         type=str,
         default="openai",
         choices=["openai"],
@@ -287,7 +299,9 @@ def main():
     )
 
     parser.add_argument(
+        "-m",
         "--openai_model",
+        dest="openai_model",
         type=str,
         help="The OpenAI LLM Model that you would like to use.",
         default="gpt-3.5-turbo-0125",
@@ -296,7 +310,7 @@ def main():
     # Parse the command line arguments
     args = parser.parse_args()
     if args.backend == "openai":
-        llm = OpenAILLMInterface(args.openai_model)
+        llm = OpenAILLMInterface(args.openai_model, args.key)
     else:
         raise NotImplementedError(
             f"The LLM backend '{args.backend}' is not supported."
diff --git a/llmpeg/openai_llm.py b/llmpeg/openai_llm.py
index 510a4ee..5cb64da 100644
--- a/llmpeg/openai_llm.py
+++ b/llmpeg/openai_llm.py
@@ -8,16 +8,17 @@
 class OpenAILLMInterface(LLMInterface):
     """Implementation of LLMInterface for OpenAI LLM API."""
 
-    def __init__(self, model_string: str):
+    def __init__(self, model_string: str, api_key: str = None):
         """Initialize OpenAI API connection and create message history.
 
         Args:
             model_string (str): The specific model to be used in API.
+            api_key (str, optional): The OpenAI API key. Defaults to None.
         """
         self._model_string = model_string
 
         try:
-            self.client = OpenAI()
+            self.client = OpenAI(api_key=api_key)
         except OpenAIError as e:
             print(
                 f"OpenAI API Unable to initialize, likely due to missing API Key environment Variable: {e}",  # noqa: E501
@@ -66,13 +67,18 @@ def invoke_model(self) -> str:
         Returns:
             str: The output generated by the language model.
         """
-        response = self.client.chat.completions.create(
-            model=self._model_string,
-            response_format={"type": "json_object"},
-            messages=self.history,
-            temperature=0.2,
-            top_p=0.2,
-        )
+        try:
+            response = self.client.chat.completions.create(
+                model=self._model_string,
+                response_format={"type": "json_object"},
+                messages=self.history,
+                temperature=0.2,
+                top_p=0.2,
+            )
+
+        except OpenAIError as e:
+            print(f"OpenAI API Error\nError code:- {e.code}\nMessage:- {e.body.get('message')}")
+            exit(1)
 
         # Extract the LLM's decision from the response
         raw_json_string = response.choices[0].message.content
diff --git a/setup.py b/setup.py
index 47e639c..024b2ed 100644
--- a/setup.py
+++ b/setup.py
@@ -7,7 +7,7 @@
     packages=find_packages(),
     include_package_data=True,
     install_requires=[
-        # Dependencies here, e.g., 'requests'
+        'openai'
     ],
     entry_points={
         "console_scripts": [