diff --git a/run_summary_export/src/run_summary_export/cli.py b/run_summary_export/src/run_summary_export/cli.py
new file mode 100644
index 0000000..b9a996c
--- /dev/null
+++ b/run_summary_export/src/run_summary_export/cli.py
@@ -0,0 +1,71 @@
+import argparse
+import json
+import os
+from pathlib import Path
+from typing import Any, List
+
+from run_summary_export.core import export_summary, RunSummary
+
+
+# CLI entrypoint for Run Summary Export Tool
+def _load_input(path: str) -> List[RunSummary]:
+    with open(path, 'r', encoding='utf-8') as f:
+        data = json.load(f)
+
+    # validate structure
+    if isinstance(data, dict):
+        data = [data]
+    if not isinstance(data, list):
+        raise ValueError('Input JSON must be an object or list of objects.')
+    
+    summaries: List[RunSummary] = []
+    for item in data:
+        if not isinstance(item, dict):
+            raise ValueError('Each entry must be a dict.')
+        missing_fields = [fld for fld in ('run_id', 'p95', 'p99', 'retry_free_count', 'publish_reorder_count') if fld not in item]
+        if missing_fields:
+            raise ValueError(f'Missing fields in input: {missing_fields}')
+        summaries.append(
+            RunSummary(
+                run_id=str(item['run_id']),
+                p95=float(item['p95']),
+                p99=float(item['p99']),
+                retry_free_count=int(item['retry_free_count']),
+                publish_reorder_count=int(item['publish_reorder_count'])
+            )
+        )
+    return summaries
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description='Run Summary Export Tool')
+    parser.add_argument('--input', required=True, help='Pfad zur JSON-Datei mit Run-Summary-Daten.')
+    parser.add_argument('--format', required=True, choices=['csv', 'json'], help="Ausgabeformat ('csv' oder 'json').")
+    parser.add_argument('--output', required=False, help='Zielpfad der Exportdatei.')
+
+    args = parser.parse_args()
+
+    input_path = args.input
+    output_format = args.format.lower()
+    output_path = args.output
+
+    if not os.path.exists(input_path):
+        raise FileNotFoundError(f'Input file not found: {input_path}')
+
+    summaries = _load_input(input_path)
+
+    export_path = export_summary(summaries, output_format)
+
+    if output_path and export_path:
+        # rename/move the generated file to the user-provided output path
+        os.replace(export_path, output_path)
+        export_path = output_path
+
+    if export_path is None:
+        raise SystemExit(f'Export failed: unsupported format {output_format!r}')
+
+    print(f'Export completed successfully -> {export_path}')
+
+
+if __name__ == '__main__':
+    main()