diff --git a/rts/motoko-rts/src/idl.rs b/rts/motoko-rts/src/idl.rs
index 1f94fe8ab7e..67ec9578f12 100644
--- a/rts/motoko-rts/src/idl.rs
+++ b/rts/motoko-rts/src/idl.rs
@@ -100,7 +100,9 @@ unsafe fn parse_idl_header<M: Memory>(
     main_types_out: *mut *mut u8,
 ) {
     if (*buf).ptr == (*buf).end {
-        idl_trap_with("empty input");
+        idl_trap_with(
+            "empty input. Expected Candid-encoded argument, but received a zero-length argument",
+        );
     }
 
     // Magic bytes (DIDL)
diff --git a/test/run-drun/ok/issue-1847.drun-run.ok b/test/run-drun/ok/issue-1847.drun-run.ok
index 111d1153446..e72ff1ec5dd 100644
--- a/test/run-drun/ok/issue-1847.drun-run.ok
+++ b/test/run-drun/ok/issue-1847.drun-run.ok
@@ -1,2 +1,2 @@
 ingress Completed: Reply: 0x4449444c016c01b3c4b1f204680100010a00000000000000000101
-ingress Err: IC0503: Canister rwlgt-iiaaa-aaaaa-aaaaa-cai trapped explicitly: IDL error: empty input
+ingress Err: IC0503: Canister rwlgt-iiaaa-aaaaa-aaaaa-cai trapped explicitly: IDL error: empty input. Expected Candid-encoded argument, but received a zero-length argument
diff --git a/test/run-drun/ok/issue-1847.ic-ref-run.ok b/test/run-drun/ok/issue-1847.ic-ref-run.ok
index e0c309cf163..78cacc8bc00 100644
--- a/test/run-drun/ok/issue-1847.ic-ref-run.ok
+++ b/test/run-drun/ok/issue-1847.ic-ref-run.ok
@@ -1,4 +1,4 @@
 → update create_canister(record {dnczaeh = null})
 ← replied: (record {hymijyo = principal "cvccv-qqaaq-aaaaa-aaaaa-c"})
 → update install_code(record {arg = blob ""; kca_xin = blob "\00asm\01\00\00\00\0…
-← rejected (RC_CANISTER_ERROR): Initialization trapped: EvalTrapError region:0xXXX-0xXXX "canister trapped explicitly: IDL error: empty input"
+← rejected (RC_CANISTER_ERROR): Initialization trapped: EvalTrapError region:0xXXX-0xXXX "canister trapped explicitly: IDL error: empty input. Expected Candid-encoded argument, but received a zero-length argument"