diff --git a/tests/src/psa_exercise_key.c b/tests/src/psa_exercise_key.c
index db3651d..3d2dfc6 100644
--- a/tests/src/psa_exercise_key.c
+++ b/tests/src/psa_exercise_key.c
@@ -623,15 +623,39 @@
                                        psa_algorithm_t alg )
 {
     psa_key_derivation_operation_t operation = PSA_KEY_DERIVATION_OPERATION_INIT;
+    unsigned char input[1];
     unsigned char output[1];
     int ok = 0;
+    psa_algorithm_t kdf_alg = PSA_ALG_KEY_AGREEMENT_GET_KDF( alg );
 
     if( usage & PSA_KEY_USAGE_DERIVE )
     {
         /* We need two keys to exercise key agreement. Exercise the
          * private key against its own public key. */
         PSA_ASSERT( psa_key_derivation_setup( &operation, alg ) );
+        if( PSA_ALG_IS_TLS12_PRF( kdf_alg ) ||
+            PSA_ALG_IS_TLS12_PSK_TO_MS( kdf_alg ) )
+        {
+            PSA_ASSERT( psa_key_derivation_input_bytes(
+                            &operation, PSA_KEY_DERIVATION_INPUT_SEED,
+                            input, sizeof( input ) ) );
+        }
+
         PSA_ASSERT( mbedtls_test_psa_key_agreement_with_self( &operation, key ) );
+
+        if( PSA_ALG_IS_TLS12_PRF( kdf_alg ) ||
+            PSA_ALG_IS_TLS12_PSK_TO_MS( kdf_alg ) )
+        {
+            PSA_ASSERT( psa_key_derivation_input_bytes(
+                            &operation, PSA_KEY_DERIVATION_INPUT_LABEL,
+                            input, sizeof( input ) ) );
+        }
+        else if( PSA_ALG_IS_HKDF( kdf_alg ) )
+        {
+            PSA_ASSERT( psa_key_derivation_input_bytes(
+                            &operation, PSA_KEY_DERIVATION_INPUT_INFO,
+                            input, sizeof( input ) ) );
+        }
         PSA_ASSERT( psa_key_derivation_output_bytes( &operation,
                                                      output,
                                                      sizeof( output ) ) );