diff --git a/orchard_poseidon.py b/orchard_poseidon.py
index b510c2e..c091f97 100644
--- a/orchard_poseidon.py
+++ b/orchard_poseidon.py
@@ -254,6 +254,7 @@ ROUND_CONSTANTS = [
     Fp(0x2166389a0e4e1f364627f44f183c91e19a0f302972d3b542faae23893d5f50fd),
     Fp(0x0ade42a791fef5cf2c386d2df993e84538576cf565d379e8a3be16b562d755c2)
 ]
+assert len(ROUND_CONSTANTS) == (R_F + R_P) * t
 
 # MDS matrix generated by the reference implementation script, commit 659de89
 # https://extgit.iaik.tugraz.at/krypto/hadeshash/-/blob/master/code/generate_parameters_grain.sage
@@ -316,12 +317,12 @@ def main():
         render_args(),
         'orchard_poseidon',
         (
-            ('input', '[[u8; 32]; 3]'),
-            ('output', '[[u8; 32]; 3]'),
+            ('initial_state', '[[u8; 32]; 3]'),
+            ('final_state', '[[u8; 32]; 3]'),
         ),
         [{
-            'input': list(map(bytes, input)),
-            'output': list(map(bytes, perm(input))),
+            'initial_state': list(map(bytes, input)),
+            'final_state': list(map(bytes, perm(input))),
         } for input in test_vectors],
     )