diff --git a/src/semgrep_mcp/server.py b/src/semgrep_mcp/server.py
index 3798da1..ed8fc8c 100755
--- a/src/semgrep_mcp/server.py
+++ b/src/semgrep_mcp/server.py
@@ -293,6 +293,8 @@ def get_semgrep_scan_args(temp_dir: str, config: str | None = None) -> list[str]
     # if no config is provided to allow for either the default "auto"
     # or whatever the logged in config is
     args = ["scan", "--json", "--experimental"]  # avoid the extra exec
+    if os.environ.get("SEMGREP_API_TOKEN"):
+        args.extend(["--pro"]) # TODO don't download the pro engine binaries
     if config:
         args.extend(["--config", config])
     args.append(temp_dir)