diff --git a/pymongo/auth_oidc.py b/pymongo/auth_oidc.py
index 543dc0200..a3afbdb3f 100644
--- a/pymongo/auth_oidc.py
+++ b/pymongo/auth_oidc.py
@@ -13,11 +13,13 @@
 # limitations under the License.
 
 """MONGODB-OIDC Authentication helpers."""
+from __future__ import annotations
+
 import os
 import threading
 from dataclasses import dataclass, field
 from datetime import datetime, timedelta, timezone
-from typing import Callable, Dict, List, Optional
+from typing import TYPE_CHECKING, Any, Callable, Dict, List, Mapping, Optional, Tuple
 
 import bson
 from bson.binary import Binary
@@ -25,6 +27,10 @@ from bson.son import SON
 from pymongo.errors import ConfigurationError, OperationFailure
 from pymongo.helpers import _REAUTHENTICATION_REQUIRED_CODE
 
+if TYPE_CHECKING:
+    from pymongo.auth import MongoCredential
+    from pymongo.pool import SocketInfo
+
 
 @dataclass
 class _OIDCProperties:
@@ -44,7 +50,9 @@ CALLBACK_VERSION = 0
 _CACHE: Dict[str, "_OIDCAuthenticator"] = {}
 
 
-def _get_authenticator(credentials, address):
+def _get_authenticator(
+    credentials: MongoCredential, address: Tuple[str, int]
+) -> _OIDCAuthenticator:
     # Clear out old items in the cache.
     now_utc = datetime.now(timezone.utc)
     to_remove = []
@@ -81,7 +89,7 @@ def _get_authenticator(credentials, address):
     return _CACHE[cache_key]
 
 
-def _get_cache_exp():
+def _get_cache_exp() -> datetime:
     return datetime.now(timezone.utc) + timedelta(minutes=CACHE_TIMEOUT_MINUTES)
 
 
@@ -98,7 +106,7 @@ class _OIDCAuthenticator:
     cache_exp_utc: datetime = field(default_factory=_get_cache_exp)
     lock: threading.Lock = field(default_factory=threading.Lock)
 
-    def get_current_token(self, use_callbacks=True):
+    def get_current_token(self, use_callbacks: bool = True) -> Optional[str]:
         properties = self.properties
 
         request_cb = properties.request_token_callback
@@ -116,16 +124,15 @@ class _OIDCAuthenticator:
                 current_valid_token = True
 
         timeout = CALLBACK_TIMEOUT_SECONDS
-
         if not use_callbacks and not current_valid_token:
             return None
 
         if not current_valid_token and request_cb is not None:
-            prev_token = self.idp_resp and self.idp_resp["access_token"]
+            prev_token = self.idp_resp["access_token"] if self.idp_resp else None
             with self.lock:
                 # See if the token was changed while we were waiting for the
                 # lock.
-                new_token = self.idp_resp and self.idp_resp["access_token"]
+                new_token = self.idp_resp["access_token"] if self.idp_resp else None
                 if new_token != prev_token:
                     return new_token
 
@@ -173,14 +180,14 @@ class _OIDCAuthenticator:
 
         return token
 
-    def auth_start_cmd(self, use_callbacks=True):
+    def auth_start_cmd(self, use_callbacks: bool = True) -> Optional[SON[str, Any]]:
         properties = self.properties
 
         # Handle aws provider credentials.
         if properties.provider_name == "aws":
             aws_identity_file = os.environ["AWS_WEB_IDENTITY_TOKEN_FILE"]
             with open(aws_identity_file) as fid:
-                token = fid.read().strip()
+                token: Optional[str] = fid.read().strip()
             payload = {"jwt": token}
             cmd = SON(
                 [
@@ -230,14 +237,16 @@ class _OIDCAuthenticator:
             ]
         )
 
-    def clear(self):
+    def clear(self) -> None:
         self.idp_info = None
         self.idp_resp = None
         self.token_exp_utc = None
 
-    def run_command(self, sock_info, cmd):
+    def run_command(
+        self, sock_info: SocketInfo, cmd: Mapping[str, Any]
+    ) -> Optional[Mapping[str, Any]]:
         try:
-            return sock_info.command("$external", cmd, no_reauth=True)
+            return sock_info.command("$external", cmd, no_reauth=True)  # type: ignore[call-arg]
         except OperationFailure as exc:
             self.clear()
             if exc.code == _REAUTHENTICATION_REQUIRED_CODE:
@@ -247,7 +256,9 @@ class _OIDCAuthenticator:
                     return self.authenticate(sock_info, reauthenticate=True)
             raise
 
-    def authenticate(self, sock_info, reauthenticate=False):
+    def authenticate(
+        self, sock_info: SocketInfo, reauthenticate: bool = False
+    ) -> Optional[Mapping[str, Any]]:
         if reauthenticate:
             prev_id = getattr(sock_info, "oidc_token_gen_id", None)
             # Check if we've already changed tokens.
@@ -264,6 +275,7 @@ class _OIDCAuthenticator:
             resp = ctx.speculative_authenticate
         else:
             cmd = self.auth_start_cmd()
+            assert cmd is not None
             resp = self.run_command(sock_info, cmd)
 
         if resp["done"]:
@@ -293,7 +305,9 @@ class _OIDCAuthenticator:
         return resp
 
 
-def _authenticate_oidc(credentials, sock_info, reauthenticate):
+def _authenticate_oidc(
+    credentials: MongoCredential, sock_info: SocketInfo, reauthenticate: bool
+) -> Optional[Mapping[str, Any]]:
     """Authenticate using MONGODB-OIDC."""
     authenticator = _get_authenticator(credentials, sock_info.address)
     return authenticator.authenticate(sock_info, reauthenticate=reauthenticate)
diff --git a/pymongo/pool.py b/pymongo/pool.py
index 2b498078c..a827d10f9 100644
--- a/pymongo/pool.py
+++ b/pymongo/pool.py
@@ -647,6 +647,7 @@ class SocketInfo:
         self.compression_settings = pool.opts._compression_settings
         self.compression_context = None
         self.socket_checker = SocketChecker()
+        self.oidc_token_gen_id = None
         # Support for mechanism negotiation on the initial handshake.
         self.negotiated_mechs = None
         self.auth_ctx = None