diff --git a/CLAUDE.md b/CLAUDE.md
index 96f4806..1bf16e7 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -79,7 +79,7 @@ tools = StackOneToolSet(include_tools=["hris_*", "!hris_create_*"])
 # Uses environment variables or direct configuration
 toolset = StackOneToolSet(
     api_key="your-api-key",  # or STACKONE_API_KEY env var
-    account_id="optional-id"  # or STACKONE_ACCOUNT_ID env var
+    account_id="optional-id"  # explicit account ID required
 )
 ```
 
diff --git a/stackone_ai/toolset.py b/stackone_ai/toolset.py
index 4e2c372..1a1cff0 100644
--- a/stackone_ai/toolset.py
+++ b/stackone_ai/toolset.py
@@ -42,7 +42,7 @@ def __init__(
 
         Args:
             api_key: Optional API key. If not provided, will try to get from STACKONE_API_KEY env var
-            account_id: Optional account ID. If not provided, will try to get from STACKONE_ACCOUNT_ID env var
+            account_id: Optional account ID
             base_url: Optional base URL override for API requests. If not provided, uses the URL from the OAS
 
         Raises:
@@ -55,7 +55,7 @@ def __init__(
                 "STACKONE_API_KEY environment variable"
             )
         self.api_key: str = api_key_value
-        self.account_id = account_id or os.getenv("STACKONE_ACCOUNT_ID")
+        self.account_id = account_id
         self.base_url = base_url
 
     def _parse_parameters(self, parameters: list[dict[str, Any]]) -> dict[str, dict[str, str]]: