diff --git a/README.md b/README.md
index 6ab146f..4b1bd2b 100755
--- a/README.md
+++ b/README.md
@@ -4,4 +4,8 @@ Named as an oblique half-pun on both tantri as a form of generating, and tantri
 
 ## dev
 
-Build with `just`, preferred over `do.sh` I think.
\ No newline at end of file
+Build with `just`, preferred over `do.sh` I think.
+
+## CLI
+
+the json files for dots and dipoles have a specific format that ignores extraneous data but is sad about missing fields.
\ No newline at end of file
diff --git a/tantri/cli/__init__.py b/tantri/cli/__init__.py
index 74bc613..58bbbe6 100755
--- a/tantri/cli/__init__.py
+++ b/tantri/cli/__init__.py
@@ -8,27 +8,33 @@ LOG_PATTERN = "%(asctime)s | %(levelname)-7s | %(name)s | %(message)s"
 
 
 def _set_up_logging(filename):
+	handlers = [logging.StreamHandler()]
+	if filename is not None:
+		handlers.append(logging.FileHandler(filename)) # type: ignore idk what the typing issue is
 	logging.basicConfig(
 		level=logging.DEBUG,
 		format=LOG_PATTERN,
-		handlers=[logging.StreamHandler(), logging.FileHandler(filename)],
+		handlers=handlers,
 	)
 	logging.getLogger("pdme").setLevel(logging.INFO)
 	logging.captureWarnings(True)
 
 
 @click.group()
+@click.option("--log", help="Enable logging to stream only", is_flag=True, default=False)
+@click.option("--log-file", help="A filename to use for logging (implies --log)")
 @click.version_option(tantri.get_version())
-@click.option("--log-file", help="A filename to use for logging")
-def cli(log_file):
-	print("hi")
-	if log_file is not None:
+def cli(log, log_file):
+	if log or (log_file is not None):
 		# log file has been provided, let's log
 		_set_up_logging(log_file)
 	_logger.info("cli")
 
 
 @cli.command()
-def hello():
+@click.option("--dipoles-file", default="dipoles.json", help="Filename containing json array of dipoles")
+@click.option("--dots-file", default="dots.json", help="Filename containing json array of dots")
+def hello(dipoles_file, dots_file):
 	_logger.info("in hello")
-	print("in hello")
+	_logger.info(f"Received parameters [dipoles_file: {dipoles_file}] and [dots_file: {dots_file}]")
+	click.echo("in hello")