diff --git a/src/LineageTree/lineageTree.py b/src/LineageTree/lineageTree.py
index 409cc6a..e8629ca 100644
--- a/src/LineageTree/lineageTree.py
+++ b/src/LineageTree/lineageTree.py
@@ -2668,7 +2668,7 @@ def nodes_at_t(
         self,
         t: int,
         r: int | Iterable[int] | None = None,
-    ) -> list:
+    ) -> list[int]:
         """
         Returns the list of nodes at time `t` that are spawn by the node(s) `r`.
 
@@ -2681,8 +2681,8 @@ def nodes_at_t(
 
         Returns
         -------
-        list
-            list of nodes at time `t` spawned by `r`
+        list of int
+            list of ids of the nodes at time `t` spawned by `r`
         """
         if not r and r != 0:
             r = {root for root in self.roots if self.time[root] <= t}
diff --git a/src/LineageTree/lineageTreeManager.py b/src/LineageTree/lineageTreeManager.py
index 7847059..41c3677 100644
--- a/src/LineageTree/lineageTreeManager.py
+++ b/src/LineageTree/lineageTreeManager.py
@@ -3,7 +3,7 @@
 import os
 import pickle as pkl
 import warnings
-from collections.abc import Callable, Iterable
+from collections.abc import Callable, Iterable, Generator
 from functools import partial
 from typing import TYPE_CHECKING, Literal
 
@@ -44,18 +44,17 @@ def __init__(self, lineagetree_list: Iterable[lineageTree] = ()):
         lineagetree_list: Iterable of lineageTree
             List of lineage trees to be in the lineageTreeManager
         """
-        self.lineagetrees = {}
-        self.lineageTree_counter = 0
-        self.registered = {}
-        self._comparisons = {}
+        self.lineagetrees: dict[str, lineageTree] = {}
+        self.lineageTree_counter: int = 0
+        self._comparisons: dict = {}
         for lT in lineagetree_list:
             self.add(lT)
 
-    def __next__(self):
+    def __next__(self) -> int:
         self.lineageTree_counter += 1
         return self.lineageTree_counter - 1
 
-    def __len__(self):
+    def __len__(self) -> int:
         """Returns how many lineagetrees are in the manager.
 
         Returns
@@ -65,10 +64,10 @@ def __len__(self):
         """
         return len(self.lineagetrees)
 
-    def __iter__(self):
+    def __iter__(self) -> Generator[tuple[str, lineageTree]]:
         yield from self.lineagetrees.items()
 
-    def __getitem__(self, key):
+    def __getitem__(self, key: str) -> lineageTree:
         if key in self.lineagetrees:
             return self.lineagetrees[key]
         else:
@@ -130,7 +129,7 @@ def add(self, other_tree: lineageTree, name: str = ""):
                 "Please add a LineageTree object or add time resolution to the LineageTree added."
             )
 
-    def __add__(self, other):
+    def __add__(self, other: lineageTree):
         self.add(other)
 
     def write(self, fname: str):
@@ -154,7 +153,7 @@ def write(self, fname: str):
             pkl.dump(self, f)
             f.close()
 
-    def remove_embryo(self, key):
+    def remove_embryo(self, key: str):
         """Removes the embryo from the manager.
 
         Parameters
@@ -429,13 +428,7 @@ def cross_lineage_edit_distance(
         -------
         Alignment
             The alignment between the nodes by the subtrees spawned by the nodes n1,n2 and the normalization function.`
-        --
-        ΟΡ
-        --
-
-        Alignment
-            The alignment between the nodes by the subtrees spawned by the nodes n1,n2 and the normalization function.`
-        tuple(tree,tree)
+        tuple(tree,tree), optional
             The two trees that have been mapped to each other.
         """