diff --git a/src/codegen/gscli/backend/typestub_utils.py b/src/codegen/gscli/backend/typestub_utils.py
index 4bab38674..d8bd51482 100644
--- a/src/codegen/gscli/backend/typestub_utils.py
+++ b/src/codegen/gscli/backend/typestub_utils.py
@@ -3,6 +3,7 @@
 import re
 from collections.abc import Callable
 from concurrent.futures import ThreadPoolExecutor
+from typing import TypeVar, Union
 
 import astor
 
@@ -10,6 +11,9 @@
 
 logger = get_logger(__name__)
 
+# Define a type variable for AST nodes
+ASTNode = TypeVar("ASTNode", ast.FunctionDef, ast.AnnAssign, ast.Assign)
+
 
 class MethodRemover(ast.NodeTransformer):
     def __init__(self, conditions: list[Callable[[ast.FunctionDef], bool]]):
@@ -44,7 +48,7 @@ def should_remove(self, node: ast.FunctionDef | ast.AnnAssign) -> bool:
 
 
 class FieldRemover(ast.NodeTransformer):
-    def __init__(self, conditions: list[Callable[[ast.FunctionDef], bool]]):
+    def __init__(self, conditions: list[Callable[[Union[ast.AnnAssign, ast.Assign]], bool]]):
         self.conditions = conditions
 
     def visit_ClassDef(self, node: ast.ClassDef) -> ast.ClassDef:
@@ -79,20 +83,22 @@ def _remove_methods(source: str, conditions: list[Callable[[ast.FunctionDef], bo
     return astor.to_source(modified_tree)
 
 
-def _remove_fields(source: str, conditions: list[Callable[[ast.FunctionDef], bool]]) -> str:
+def _remove_fields(source: str, conditions: list[Callable[[Union[ast.AnnAssign, ast.Assign]], bool]]) -> str:
     tree = ast.parse(source)
     transformer = FieldRemover(conditions)
     modified_tree = transformer.visit(tree)
     return astor.to_source(modified_tree)
 
 
-def _starts_with_underscore(node: ast.FunctionDef | ast.AnnAssign | ast.Assign) -> bool:
+def _starts_with_underscore(node: Union[ast.FunctionDef, ast.AnnAssign, ast.Assign]) -> bool:
     if isinstance(node, ast.FunctionDef):
         return node.name.startswith("_") and (not node.name.startswith("__") and not node.name.endswith("__"))
     elif isinstance(node, ast.Assign):
-        return node.targets[0].id.startswith("_")
+        if isinstance(node.targets[0], ast.Name):
+            return node.targets[0].id.startswith("_")
     elif isinstance(node, ast.AnnAssign):
-        return node.target.id.startswith("_")
+        if isinstance(node.target, ast.Name):
+            return node.target.id.startswith("_")
     return False
 
 
@@ -121,7 +127,9 @@ def _strip_internal_symbols(file: str, root: str) -> None:
             _has_decorator("noapidoc"),
         ]
 
-        modified_content = _remove_fields(original_content, [_starts_with_underscore])
+        # Type cast _starts_with_underscore to the correct type for _remove_fields
+        field_condition = _starts_with_underscore
+        modified_content = _remove_fields(original_content, [field_condition])
         modified_content = _remove_methods(modified_content, conditions)
 
         if modified_content.strip().endswith(":"):
diff --git a/src/codegen/gscli/generate/commands.py b/src/codegen/gscli/generate/commands.py
index 3f96419ff..8a90d0a40 100644
--- a/src/codegen/gscli/generate/commands.py
+++ b/src/codegen/gscli/generate/commands.py
@@ -2,6 +2,8 @@
 import os
 import re
 import shutil
+import sys
+from typing import Any
 
 import click
 from termcolor import colored
@@ -66,7 +68,7 @@ def _generate_codebase_typestubs() -> None:
     # right now this command expects you to run it from here
     if not initial_dir.endswith("codegen/codegen-backend"):
         print(colored("Error: Must be in a directory ending with 'codegen/codegen-backend'", "red"))
-        exit(1)
+        sys.exit(1)
 
     out_dir = os.path.abspath(os.path.join(initial_dir, "typings"))
     frontend_typestubs_dir = os.path.abspath(os.path.join(initial_dir, os.pardir, "codegen-frontend/assets/typestubs/graphsitter"))
@@ -113,6 +115,7 @@ def generate_docs(docs_dir: str) -> None:
 @generate.command()
 @click.argument("filepath", default=sdk.__path__[0] + "/system-prompt.txt", required=False)
 def system_prompt(filepath: str) -> None:
+    """Generate the system prompt and write it to the specified file"""
     print(f"Generating system prompt and writing to {filepath}...")
     new_system_prompt = get_system_prompt()
     with open(filepath, "w") as f:
@@ -121,6 +124,7 @@ def system_prompt(filepath: str) -> None:
 
 
 def get_snippet_pattern(target_name: str) -> str:
+    """Generate a regex pattern to match code snippets with the given target name"""
     pattern = rf"\[//\]: # \(--{re.escape(target_name)}--\)\s*(?:\[//\]: # \(--{re.escape(AUTO_GENERATED_COMMENT)}--\)\s*)?"
     pattern += CODE_SNIPPETS_REGEX
     return pattern
@@ -153,9 +157,9 @@ def generate_codegen_sdk_docs(docs_dir: str) -> None:
 
     # Write the generated docs to the file system, splitting between core, python, and typescript
     # keep track of where we put each one so we can update the mint.json
-    python_set = set()
-    typescript_set = set()
-    core_set = set()
+    python_set: set[str] = set()
+    typescript_set: set[str] = set()
+    core_set: set[str] = set()
     # TODO replace this with new `get_mdx_for_class` function
     for class_doc in gs_docs.classes:
         class_name = class_doc.title
@@ -178,7 +182,7 @@ def generate_codegen_sdk_docs(docs_dir: str) -> None:
     # Update the core, python, and typescript page sets in mint.json
     mint_file_path = os.path.join(docs_dir, "mint.json")
     with open(mint_file_path) as mint_file:
-        mint_data = json.load(mint_file)
+        mint_data: dict[str, Any] = json.load(mint_file)
 
     # Find the "Codebase SDK" group where we want to add the pages
     codebase_sdk_group = next(group for group in mint_data["navigation"] if group["group"] == "API Reference")
diff --git a/src/codegen/gscli/generate/runner_imports.py b/src/codegen/gscli/generate/runner_imports.py
index d07b86062..e05fde711 100644
--- a/src/codegen/gscli/generate/runner_imports.py
+++ b/src/codegen/gscli/generate/runner_imports.py
@@ -51,9 +51,9 @@ def get_generated_imports():
 )
 
 
-def fix_ruff_imports(objects: list[DocumentedObject]):
+def fix_ruff_imports(objects: list[DocumentedObject]) -> None:
     root, _ = split_git_path(str(Path(__file__)))
-    to_add = []
+    to_add: list[str] = []
     for obj in objects:
         to_add.append(f"{obj.module}.{obj.name}")
     generics = tomlkit.array()
@@ -66,12 +66,12 @@ def fix_ruff_imports(objects: list[DocumentedObject]):
     config.write_text(tomlkit.dumps(toml_config))
 
 
-def get_runner_imports(include_codegen=True, include_private_imports: bool = True) -> str:
+def get_runner_imports(include_codegen: bool = True, include_private_imports: bool = True) -> str:
     # get the imports from the apidoc, py_apidoc, and ts_apidoc
     gs_objects = get_documented_objects()
     gs_public_objects = list(chain(gs_objects["apidoc"], gs_objects["py_apidoc"], gs_objects["ts_apidoc"]))
     fix_ruff_imports(gs_public_objects)
-    gs_public_imports = {f"from {obj.module} import {obj.name}" for obj in gs_public_objects}
+    gs_public_imports: set[str] = {f"from {obj.module} import {obj.name}" for obj in gs_public_objects}
 
     # construct import string with all imports
     ret = IMPORT_STRING_TEMPLATE.format(
diff --git a/src/codegen/gscli/generate/system_prompt.py b/src/codegen/gscli/generate/system_prompt.py
index 33b4a18a5..988a3afa4 100644
--- a/src/codegen/gscli/generate/system_prompt.py
+++ b/src/codegen/gscli/generate/system_prompt.py
@@ -1,27 +1,35 @@
 import json
 from pathlib import Path
+from typing import Any, Optional
 
 docs = Path("./docs")
-mint = json.load(open(docs / "mint.json"))
+mint: dict[str, Any] = json.load(open(docs / "mint.json"))
 
 
-def render_page(page_str: str):
+def render_page(page_str: str) -> str:
+    """Render a single page from the docs"""
     return open(docs / (page_str + ".mdx")).read()
 
 
-def render_group(page_strs: list[str]):
+def render_group(page_strs: list[str]) -> str:
+    """Render a group of pages from the docs"""
     return "\n\n".join([render_page(x) for x in page_strs])
 
 
-def get_group(name) -> list[str]:
+def get_group(name: str) -> Optional[list[str]]:
+    """Get a group of pages by name from the mint.json file"""
     group = next((x for x in mint["navigation"] if x.get("group") == name), None)
     if group:
         return group["pages"]
+    return None
 
 
 def render_groups(group_names: list[str]) -> str:
+    """Render multiple groups of pages from the docs"""
     groups = [get_group(x) for x in group_names]
-    return "\n\n".join([render_group(g) for g in groups])
+    # Filter out None values
+    filtered_groups = [g for g in groups if g is not None]
+    return "\n\n".join([render_group(g) for g in filtered_groups])
 
 
 def get_system_prompt() -> str:
diff --git a/src/codegen/gscli/generate/utils.py b/src/codegen/gscli/generate/utils.py
index d579f9288..af053a8e2 100644
--- a/src/codegen/gscli/generate/utils.py
+++ b/src/codegen/gscli/generate/utils.py
@@ -12,11 +12,11 @@ class LanguageType(StrEnum):
     BOTH = "BOTH"
 
 
-def generate_builtins_file(path_to_builtins: str, language_type: LanguageType):
+def generate_builtins_file(path_to_builtins: str, language_type: LanguageType) -> None:
     """Generates and writes the builtins file"""
     documented_imports = get_documented_objects()
     all_objects = chain(documented_imports["apidoc"], documented_imports["py_apidoc"], documented_imports["ts_apidoc"])
-    unique_imports = {f"from {obj.module} import {obj.name} as {obj.name}" for obj in all_objects}
+    unique_imports: set[str] = {f"from {obj.module} import {obj.name} as {obj.name}" for obj in all_objects}
     all_imports = "\n".join(sorted(unique_imports))
     # TODO: re-use code with runner_imports list
     # TODO: also auto generate import string for CodemodContext + MessageType