diff --git a/README.md b/README.md
index b8e49de..2695ffe 100644
--- a/README.md
+++ b/README.md
@@ -39,11 +39,6 @@ project_return_schema = client.projects.create(
 print(project_return_schema.id)
 ```
 
-While you can provide an `api_key` keyword argument,
-we recommend using [python-dotenv](https://pypi.org/project/python-dotenv/)
-to add `CODEX_API_KEY="My API Key"` to your `.env` file
-so that your API Key is not stored in source control.
-
 ## Async usage
 
 Simply import `AsyncCodex` instead of `Codex` and use `await` with each API call:
diff --git a/src/codex/_client.py b/src/codex/_client.py
index 843f6a2..09aaafd 100644
--- a/src/codex/_client.py
+++ b/src/codex/_client.py
@@ -95,18 +95,9 @@ def __init__(
         # part of our public interface in the future.
         _strict_response_validation: bool = False,
     ) -> None:
-        """Construct a new synchronous Codex client instance.
-
-        This automatically infers the following arguments from their corresponding environment variables if they are not provided:
-        - `api_key` from `CODEX_API_KEY`
-        - `access_key` from `CODEX_ACCESS_KEY`
-        """
-        if api_key is None:
-            api_key = os.environ.get("CODEX_API_KEY")
+        """Construct a new synchronous Codex client instance."""
         self.api_key = api_key
 
-        if access_key is None:
-            access_key = os.environ.get("CODEX_ACCESS_KEY")
         self.access_key = access_key
 
         self._environment = environment
@@ -334,18 +325,9 @@ def __init__(
         # part of our public interface in the future.
         _strict_response_validation: bool = False,
     ) -> None:
-        """Construct a new async Codex client instance.
-
-        This automatically infers the following arguments from their corresponding environment variables if they are not provided:
-        - `api_key` from `CODEX_API_KEY`
-        - `access_key` from `CODEX_ACCESS_KEY`
-        """
-        if api_key is None:
-            api_key = os.environ.get("CODEX_API_KEY")
+        """Construct a new async Codex client instance."""
         self.api_key = api_key
 
-        if access_key is None:
-            access_key = os.environ.get("CODEX_ACCESS_KEY")
         self.access_key = access_key
 
         self._environment = environment