diff --git a/src/scirpy/pl/_logoplots.py b/src/scirpy/pl/_logoplots.py
index 0f8e10baa..c8a06f150 100644
--- a/src/scirpy/pl/_logoplots.py
+++ b/src/scirpy/pl/_logoplots.py
@@ -13,10 +13,11 @@
 @DataHandler.inject_param_docs()
 def logoplot_cdr3_motif(
     adata: DataHandler.TYPE,
+    *,
     chains: Literal["VJ_1", "VDJ_1", "VJ_2", "VDJ_2"] | Sequence[Literal["VJ_1", "VDJ_1", "VJ_2", "VDJ_2"]] = "VDJ_1",
-    airr_mod="airr",
-    airr_key="airr",
-    chain_idx_key="chain_indices",
+    airr_mod: str = "airr",
+    airr_key: str = "airr",
+    chain_idx_key: str = "chain_indices",
     cdr3_col: str = "junction_aa",
     to_type: Sequence[Literal["information", "counts", "probability", "weight"]] = "information",
     pseudocount: float = 0,