diff --git a/OTXv2.py b/OTXv2.py
index 9c14f6f..c4ec848 100755
--- a/OTXv2.py
+++ b/OTXv2.py
@@ -98,10 +98,14 @@ def __init__(
         user_agent=None, verify=True, cert=None
     ):
         self.key = api_key
+        # Validates API Key length and hexadecimal format
+        if not isinstance(api_key, str) or len(api_key) != 64 or not all(c in '0123456789abcdefABCDEF' for c in api_key):
+            raise ValueError(f"Invalid API key: '{api_key}'. Must be a 64-character hexadecimal string.")
+
         self.server = server
         self.verify = verify
         self.cert = cert
-
+        
         self.proxies = {}
         if proxy:
             self.proxies['http'] = proxy
@@ -386,12 +390,40 @@ def walkapi(self, url, iter=False, max_page=None, max_items=None, method='GET',
 
     def getall(self, modified_since=None, author_name=None, limit=50, max_page=None, max_items=None, iter=False):
         """
-        Get all pulses user is subscribed to.
+        Get all pulses the user is subscribed to.
         :param modified_since: datetime object representing earliest date you want returned in results
         :param author_name: Name of pulse author to limit results to
         :param limit: The page size to retrieve in a single request
-        :return: the consolidated set of pulses for the user
+        :return: 
+            :list or iterator: If iter=False, a list of pulse dicts; if iter=True, an iterator over pulses.
+            :list: 
+                - id (str): Pulse identifier (24-char hex)
+                - name (str): Pulse name
+                - description (str, optional): Pulse description
+                - author_name (str): Author’s username
+                - public (str): Defaults to 'True'
+                - revision (int): Revision number
+                - adversary (str, optional): Adversary name
+                - industries (list): List of industries
+                - tlp (str): Traffic Light Protocol (lowercase: 'white', 'green', etc.)
+                - tags (list): List of tags
+                - created (str): ISO timestamp
+                - modified (str): ISO timestamp
+                - references (list): External references
+                - targeted_countries (list): Country codes/names
+                - indicators (list): List of indicator dicts with:
+                    - id (str): Numeric string (can exceed 32-bit int)
+                    - indicator (str): IOC value
+                    - type (str): Indicator type (e.g., 'IPv4')
+                    - title (str, optional)
+                    - description (str, optional)
+                    - created (str): ISO timestamp
+                    - is_active (int): 0 or 1
+                    - content (str, optional)
+                    - expiration (str, optional)
+                    - role (str, optional)
         """
+        
         args = {'limit': limit}
         if modified_since is not None:
             if isinstance(modified_since, (datetime.datetime, datetime.date)):