diff --git a/pyproject.toml b/pyproject.toml
index 7f9d7ab..0bb91b0 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -7,3 +7,6 @@ requires-python = ">=3.13"
 dependencies = [
     "tasklib>=2.5.1",
 ]
+
+[tool.pyright]
+typeCheckingMode = "standard"
diff --git a/topen b/topen
index 2103006..9cb6091 100755
--- a/topen
+++ b/topen
@@ -5,46 +5,123 @@
 # Edits an existing task note file,
 # or creates a new one.
 
+# It currently assumes an XDG-compliant taskwarrior configuration by default.
+
+import argparse
+import os
 import subprocess
 import sys
 from pathlib import Path
 
 from tasklib import Task, TaskWarrior
 
-TASK_DATA_DIR = "~/.local/share/task"
+# TODO: This should not assume XDG compliance for
+# no-setup TW instances.
+TASK_RC = os.getenv("TASKRC", "~/.config/task/taskrc")
+TASK_DATA_DIR = os.getenv("TASKDATA", "~/.local/share/task")
 
-TASKNOTES_DIR = "~/.local/share/task/notes"
-TASKNOTES_EXT = "md"
-TASKNOTES_ANNOT = "Note"
+TOPEN_DIR = os.getenv("TOPEN_DIR", "~/.local/share/task/notes")
+TOPEN_EXT = os.getenv("TOPEN_EXT", "md")
+TOPEN_ANNOT = os.getenv("TOPEN_ANNOT", "Note")
+TOPEN_EDITOR = os.getenv("EDITOR") or os.getenv("VISUAL", "nano")
+TOPEN_QUIET = os.getenv("TOPEN_QUIET", False)
 
-tw = TaskWarrior(data_location=TASK_DATA_DIR)
 
-args = sys.argv
+def parse_cli() -> argparse.Namespace:
+    parser = argparse.ArgumentParser(description="Taskwarrior note editing made easy.")
+    _ = parser.add_argument(
+        "id", help="The id/uuid of the taskwarrior task for which we edit notes"
+    )
+    _ = parser.add_argument(
+        "-d",
+        "--notes-dir",
+        default=TOPEN_DIR,
+        help="Location of topen notes files",
+    )
+    _ = parser.add_argument(
+        "--quiet",
+        default=TOPEN_QUIET,
+        action="store_true",
+        help="Silence any verbose displayed information",
+    )
+    _ = parser.add_argument(
+        "--extension", default=TOPEN_EXT, help="Extension of note files"
+    )
+    _ = parser.add_argument(
+        "--annotation",
+        default=TOPEN_ANNOT,
+        help="Annotation content to set within taskwarrior",
+    )
+    _ = parser.add_argument(
+        "--task-data", default=TASK_DATA_DIR, help="Location of taskwarrior data"
+    )
+    _ = parser.add_argument(
+        "--editor", default=TOPEN_EDITOR, help="Program to open note files with"
+    )
 
-if not len(args) == 2:
-    _ = sys.stderr.write("Please provide task ID as argument.\n")
-    sys.exit(1)
+    return parser.parse_args()
 
-given_id = args[1]
 
-try:
-    t = tw.tasks.get(id=given_id)
-except Task.DoesNotExist:
-    t = tw.tasks.get(uuid=given_id)
+IS_QUIET = False
 
-_ = sys.stderr.write(f"Editing note for: {t['description']} ({t['uuid']})\n")
 
-notes_file = Path(TASKNOTES_DIR).joinpath(f"{t['uuid']}.{TASKNOTES_EXT}")
+def whisper(text: str) -> None:
+    if not IS_QUIET:
+        print(text)
 
-proc = subprocess.Popen(f"nvim {notes_file}", shell=True)
-_ = proc.wait()
 
-def add_annotation_if_missing(task: Task) -> None:
-    for annot in t["annotations"]:
-        if annot["description"] == "Note":
+def main():
+    args = parse_cli()
+
+    if not args.id:
+        _ = sys.stderr.write("Please provide task ID as argument.\n")
+    if args.quiet:
+        global IS_QUIET
+        IS_QUIET = True
+
+    task = get_task(id=args.id, data_location=args.task_data)
+    uuid = task["uuid"]
+    if not uuid:
+        _ = sys.stderr.write(f"Could not find task for ID: {args.id}.")
+        sys.exit(1)
+    fname = get_notes_file(uuid, notes_dir=args.notes_dir, notes_ext=args.extension)
+
+    open_editor(fname, editor=args.editor)
+
+    add_annotation_if_missing(task, annotation_content=args.annotation)
+
+
+def get_task(id: str, data_location: str = TASK_DATA_DIR) -> Task:
+    tw = TaskWarrior(data_location)
+    try:
+        t = tw.tasks.get(id=id)
+    except Task.DoesNotExist:
+        t = tw.tasks.get(uuid=id)
+
+    return t
+
+
+def get_notes_file(
+    uuid: str, notes_dir: str = TOPEN_DIR, notes_ext: str = TOPEN_EXT
+) -> Path:
+    return Path(notes_dir).joinpath(f"{uuid}.{notes_ext}")
+
+
+def open_editor(file: Path, editor: str = TOPEN_EDITOR) -> None:
+    _ = whisper(f"Editing note: {file}")
+    proc = subprocess.Popen(f"{editor} {file}", shell=True)
+    _ = proc.wait()
+
+
+def add_annotation_if_missing(
+    task: Task, annotation_content: str = TOPEN_ANNOT
+) -> None:
+    for annot in task["annotations"] or []:
+        if annot["description"] == annotation_content:
             return
-    t.add_annotation(TASKNOTES_ANNOT)
-    _ = sys.stderr.write(f"Added annotation.\n")
+    task.add_annotation(annotation_content)
+    _ = whisper(f"Added annotation: {annotation_content}")
 
 
-add_annotation_if_missing(t)
+if __name__ == "__main__":
+    main()