diff --git a/jni/c/headers/java/fr_acinq_secp256k1_Secp256k1CFunctions.h b/jni/c/headers/java/fr_acinq_secp256k1_Secp256k1CFunctions.h
index 0aedea0..65c685b 100644
--- a/jni/c/headers/java/fr_acinq_secp256k1_Secp256k1CFunctions.h
+++ b/jni/c/headers/java/fr_acinq_secp256k1_Secp256k1CFunctions.h
@@ -35,6 +35,13 @@ extern "C" {
 #define fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_MUSIG_KEYAGG_CACHE_SIZE 197L
 #undef fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_MUSIG_SESSION_SIZE
 #define fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_MUSIG_SESSION_SIZE 133L
+
+#undef  fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_SECRET_NONCE_SIZE
+#define fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_SECRET_NONCE_SIZE 68L
+#undef  fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_AGGREGATE_SHARE_SIZE
+#define fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_AGGREGATE_SHARE_SIZE 32L
+#undef  fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_SESSION_SIZE
+#define fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_SESSION_SIZE 133L
 /*
  * Class:     fr_acinq_secp256k1_Secp256k1CFunctions
  * Method:    secp256k1_context_create
diff --git a/jni/c/src/fr_acinq_secp256k1_Secp256k1CFunctions.c b/jni/c/src/fr_acinq_secp256k1_Secp256k1CFunctions.c
index 2651ec9..1e9d1f4 100644
--- a/jni/c/src/fr_acinq_secp256k1_Secp256k1CFunctions.c
+++ b/jni/c/src/fr_acinq_secp256k1_Secp256k1CFunctions.c
@@ -1761,6 +1761,7 @@ JNIEXPORT jbyteArray JNICALL Java_fr_acinq_secp256k1_Secp256k1CFunctions_secp256
 
   int result = 0;
 
+  CHECKRESULT((*penv)->GetArrayLength(penv, jpublicKey) != 32, "public key must be 32 bytes");
   pub = (*penv)->GetByteArrayElements(penv, jpublicKey, 0);
   result = secp256k1_xonly_pubkey_parse(ctx, &public_key, (unsigned char *)pub);
   (*penv)->ReleaseByteArrayElements(penv, jpublicKey, pub, 0);
@@ -1958,8 +1959,7 @@ JNIEXPORT jbyteArray JNICALL Java_fr_acinq_secp256k1_Secp256k1CFunctions_secp256
   }
 
   if (jpubkey != NULL) {
-    size = (*penv)->GetArrayLength(penv, jpubkey);
-    CHECKRESULT(size != 32, "invalid xonly public key size");
+    CHECKRESULT((*penv)->GetArrayLength(penv, jpubkey) != 32, "public key must be 32 bytes");
     pubkey_ptr = (*penv)->GetByteArrayElements(penv, jpubkey, 0);
     result = secp256k1_xonly_pubkey_parse(ctx, &pubkey, (unsigned char *)pubkey_ptr);
     (*penv)->ReleaseByteArrayElements(penv, jpubkey, pubkey_ptr, 0);
@@ -2071,6 +2071,7 @@ JNIEXPORT jbyteArray JNICALL Java_fr_acinq_secp256k1_Secp256k1CFunctions_secp256
   CHECKRESULT(size != 32, "invalid message size");
   copy_bytes_from_java(penv, jmsg32, size, msg32);
 
+  CHECKRESULT((*penv)->GetArrayLength(penv, jpubkey) != 32, "public key must be 32 bytes");
   pub = (*penv)->GetByteArrayElements(penv, jpubkey, 0);
   result = secp256k1_xonly_pubkey_parse(ctx, &public_key, (unsigned char *)pub);
   (*penv)->ReleaseByteArrayElements(penv, jpubkey, pub, 0);
@@ -2169,17 +2170,17 @@ JNIEXPORT jbyteArray JNICALL Java_fr_acinq_secp256k1_Secp256k1CFunctions_secp256
 
   int result = 0;
 
-  copy_bytes_from_java(penv, jsecnonce, fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_MUSIG_SECRET_NONCE_SIZE, secnonce.data);
+  CHECKRESULT((*penv)->GetArrayLength(penv, jsecnonce) != fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_SECRET_NONCE_SIZE, "invalid secnonce size");
+  copy_bytes_from_java(penv, jsecnonce, fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_SECRET_NONCE_SIZE, secnonce.data);
 
-  size = (*penv)->GetArrayLength(penv, jagg_share);
-  CHECKRESULT(size != sizeof(secp256k1_frost_share), "invalid agg_share size");
+  CHECKRESULT((*penv)->GetArrayLength(penv, jagg_share) != fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_AGGREGATE_SHARE_SIZE, "invalid agg_share size");
   in32 = (*penv)->GetByteArrayElements(penv, jagg_share, 0);
   result = secp256k1_frost_share_parse(ctx, &agg_share, (unsigned char *)in32);
   (*penv)->ReleaseByteArrayElements(penv, jagg_share, in32, 0);
   CHECKRESULT(!result, "secp256k1_frost_share_parse failed");
 
-  CHECKRESULT((*penv)->GetArrayLength(penv, jsession) != fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_MUSIG_SESSION_SIZE, "invalid session size");
-  copy_bytes_from_java(penv, jsession, fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_MUSIG_SESSION_SIZE, session.data);
+  CHECKRESULT((*penv)->GetArrayLength(penv, jsession) != fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_SESSION_SIZE, "invalid session size");
+  copy_bytes_from_java(penv, jsession, fr_acinq_secp256k1_Secp256k1CFunctions_SECP256K1_FROST_SESSION_SIZE, session.data);
 
   if (jtweak_cache != NULL) 
   {
@@ -2199,11 +2200,14 @@ JNIEXPORT jbyteArray JNICALL Java_fr_acinq_secp256k1_Secp256k1CFunctions_secp256
   );
   CHECKRESULT(!result, "secp256k1_frost_partial_sign failed");
 
-  jpsig = (*penv)->NewByteArray(penv, 32);
-  ptr = (*penv)->GetByteArrayElements(penv, jpsig, 0);
-  result = secp256k1_frost_partial_sig_serialize(ctx, (unsigned char *)ptr, &partial_sig);
+  unsigned char partial_sig_bytes[32];
+
+  result = secp256k1_frost_partial_sig_serialize(ctx, partial_sig_bytes, &partial_sig);
   CHECKRESULT(!result, "secp256k1_frost_partial_sig_serialize failed");
 
+  jpsig = (*penv)->NewByteArray(penv, 32);
+  copy_bytes_to_java(penv, jpsig, 32, partial_sig_bytes);
+
   return jpsig;
 }
 
@@ -2364,7 +2368,7 @@ JNIEXPORT jbyteArray JNICALL Java_fr_acinq_secp256k1_Secp256k1CFunctions_secp256
   free_frost_partial_sigs(psigs, count);
   CHECKRESULT(!result, "secp256k1_frost_partial_sig_agg failed");
 
-  jpsig = (*penv)->NewByteArray(penv, 64);
-  copy_bytes_to_java(penv, jpsig, 64, sig64);
-  return jpsig;
+  jbyteArray jsig = (*penv)->NewByteArray(penv, 64);
+  copy_bytes_to_java(penv, jsig, 64, sig64);
+  return jsig;
 }
\ No newline at end of file
diff --git a/tests/src/commonTest/kotlin/fr/acinq/secp256k1/FrostTest.kt b/tests/src/commonTest/kotlin/fr/acinq/secp256k1/FrostTest.kt
index c3b0c59..7c7311f 100644
--- a/tests/src/commonTest/kotlin/fr/acinq/secp256k1/FrostTest.kt
+++ b/tests/src/commonTest/kotlin/fr/acinq/secp256k1/FrostTest.kt
@@ -481,7 +481,6 @@ class FrostTest: BaseTest() {
                 signer.jsonObject["session"]!!.jsonPrimitive.content
             )
 
-
             val partialSignature = Secp256k1.frostPartialSign(
                 secNonce,
                 aggregateShare,