diff --git a/openhands/cli/main.py b/openhands/cli/main.py
index d9cbf79256..0c99ffa6ff 100644
--- a/openhands/cli/main.py
+++ b/openhands/cli/main.py
@@ -273,7 +273,6 @@ async def run_session(
 
 async def main(loop: asyncio.AbstractEventLoop) -> None:
     """Runs the agent in CLI mode."""
-
     args = parse_arguments()
 
     logger.setLevel(logging.WARNING)
diff --git a/openhands/cli/tui.py b/openhands/cli/tui.py
index e84676f83f..d7d3d615c5 100644
--- a/openhands/cli/tui.py
+++ b/openhands/cli/tui.py
@@ -15,6 +15,7 @@ from prompt_toolkit.document import Document
 from prompt_toolkit.formatted_text import HTML, FormattedText, StyleAndTextTuples
 from prompt_toolkit.input import create_input
 from prompt_toolkit.key_binding import KeyBindings
+from prompt_toolkit.key_binding.key_processor import KeyPressEvent
 from prompt_toolkit.keys import Keys
 from prompt_toolkit.layout.containers import HSplit, Window
 from prompt_toolkit.layout.controls import FormattedTextControl
@@ -70,7 +71,7 @@ print_lock = threading.Lock()
 
 
 class UsageMetrics:
-    def __init__(self):
+    def __init__(self) -> None:
         self.metrics: Metrics = Metrics()
         self.session_init_time: float = time.time()
 
@@ -78,7 +79,7 @@ class UsageMetrics:
 class CustomDiffLexer(Lexer):
     """Custom lexer for the specific diff format."""
 
-    def lex_document(self, document) -> StyleAndTextTuples:
+    def lex_document(self, document: Document) -> StyleAndTextTuples:
         lines = document.lines
 
         def get_line(lineno: int) -> StyleAndTextTuples:
@@ -427,7 +428,7 @@ def display_agent_state_change_message(agent_state: str) -> None:
 class CommandCompleter(Completer):
     """Custom completer for commands."""
 
-    def __init__(self, agent_state: str):
+    def __init__(self, agent_state: str) -> None:
         super().__init__()
         self.agent_state = agent_state
 
@@ -450,7 +451,7 @@ class CommandCompleter(Completer):
                     )
 
 
-def create_prompt_session() -> PromptSession:
+def create_prompt_session() -> PromptSession[str]:
     return PromptSession(style=DEFAULT_STYLE)
 
 
@@ -465,7 +466,7 @@ async def read_prompt_input(agent_state: str, multiline: bool = False) -> str:
             kb = KeyBindings()
 
             @kb.add('c-d')
-            def _(event) -> None:
+            def _(event: KeyPressEvent) -> None:
                 event.current_buffer.validate_and_handle()
 
             with patch_stdout():
@@ -538,11 +539,10 @@ async def process_agent_pause(done: asyncio.Event, event_stream: EventStream) ->
 def cli_confirm(
     question: str = 'Are you sure?', choices: list[str] | None = None
 ) -> int:
-    """
-    Display a confirmation prompt with the given question and choices.
+    """Display a confirmation prompt with the given question and choices.
+
     Returns the index of the selected choice.
     """
-
     if choices is None:
         choices = ['Yes', 'No']
     selected = [0]  # Using list to allow modification in closure
@@ -561,15 +561,15 @@ def cli_confirm(
     kb = KeyBindings()
 
     @kb.add('up')
-    def _(event) -> None:
+    def _(event: KeyPressEvent) -> None:
         selected[0] = (selected[0] - 1) % len(choices)
 
     @kb.add('down')
-    def _(event) -> None:
+    def _(event: KeyPressEvent) -> None:
         selected[0] = (selected[0] + 1) % len(choices)
 
     @kb.add('enter')
-    def _(event) -> None:
+    def _(event: KeyPressEvent) -> None:
         event.app.exit(result=selected[0])
 
     style = Style.from_dict({'selected': COLOR_GOLD, 'unselected': ''})
@@ -601,7 +601,7 @@ def kb_cancel() -> KeyBindings:
     bindings = KeyBindings()
 
     @bindings.add('escape')
-    def _(event) -> None:
+    def _(event: KeyPressEvent) -> None:
         event.app.exit(exception=UserCancelledError, style='class:aborting')
 
     return bindings
diff --git a/openhands/cli/utils.py b/openhands/cli/utils.py
index 276f31d614..f56b290280 100644
--- a/openhands/cli/utils.py
+++ b/openhands/cli/utils.py
@@ -78,8 +78,7 @@ class ModelInfo(BaseModel):
 
 
 def extract_model_and_provider(model: str) -> ModelInfo:
-    """
-    Extract provider and model information from a model identifier.
+    """Extract provider and model information from a model identifier.
 
     Args:
         model: The model identifier string
@@ -114,8 +113,7 @@ def extract_model_and_provider(model: str) -> ModelInfo:
 def organize_models_and_providers(
     models: list[str],
 ) -> dict[str, 'ProviderInfo']:
-    """
-    Organize a list of model identifiers by provider.
+    """Organize a list of model identifiers by provider.
 
     Args:
         models: List of model identifiers
@@ -188,7 +186,7 @@ class ProviderInfo(BaseModel):
             return self.models
         raise KeyError(f'ProviderInfo has no key {key}')
 
-    def get(self, key: str, default=None) -> str | list[str] | None:
+    def get(self, key: str, default: None = None) -> str | list[str] | None:
         """Dictionary-like get method with default value."""
         try:
             return self[key]