diff --git a/lib/aos/init.c b/lib/aos/init.c
index 3092cf8..d3746bc 100644
--- a/lib/aos/init.c
+++ b/lib/aos/init.c
@@ -109,17 +109,16 @@ static size_t aos_terminal_write(const char *buf, size_t len)
     if(len == 0) return 0;
 
     struct aos_rpc *rpc = aos_rpc_get_serial_channel();
+    if (rpc == NULL) {
+        debug_printf("[aos_terminal_write] RPC NOT YET INITIALIZED: %.*s\n", len, buf);
+        USER_PANIC("Make sure to initialize aos_rpc before barrelfish_libc_glue_init is called.");
+    }
     for (int i = 0; i < len; ++i) {
         err = aos_rpc_serial_putchar(rpc, buf[i]);
         if (err_is_fail(err)) return err;
     }
 
     return SYS_ERR_OK;
-    // if (rpc == NULL) {
-    //     debug_printf("[aos_terminal_write] RPC NOT YET INITIALIZED: %.*s\n", len, buf);
-    //     USER_PANIC("Make sure to initialize aos_rpc before barrelfish_libc_glue_init is called.");
-    // }
-
     // return aos_rpc_serial_write(rpc, buf, len);
 }
 
@@ -129,6 +128,10 @@ static size_t aos_terminal_read(char *buf, size_t len)
     if(len == 0) return 0;
 
     struct aos_rpc *rpc = aos_rpc_get_serial_channel();
+    if (rpc == NULL) {
+        debug_printf("[aos_terminal_read] RPC NOT YET INITIALIZED: %.*s\n", len, buf);
+        USER_PANIC("Make sure to initialize aos_rpc before barrelfish_libc_glue_init is called.");
+    }
     for (int i = 0; i < len; ++i) {
         char in;
         err = aos_rpc_serial_getchar(rpc, &in);
@@ -137,12 +140,6 @@ static size_t aos_terminal_read(char *buf, size_t len)
     }
 
     return SYS_ERR_OK;
-
-    // if (rpc == NULL) {
-    //     debug_printf("[aos_terminal_read] RPC NOT YET INITIALIZED: %.*s\n", len, buf);
-    //     USER_PANIC("Make sure to initialize aos_rpc before barrelfish_libc_glue_init is called.");
-    // }
-
     // return aos_rpc_serial_read(rpc, buf, len);
 }
 
diff --git a/usr/shelly/shelly_cmd.c b/usr/shelly/shelly_cmd.c
index 99d2f02..30891ac 100644
--- a/usr/shelly/shelly_cmd.c
+++ b/usr/shelly/shelly_cmd.c
@@ -12,6 +12,22 @@ static void parse_cmd_line(char * line, int * argc, char ** argv) {
     }
 }
 
+static errval_t shelly_cmd_help(char * line) {
+    errval_t err;
+    err = shelly_write_str("commands implemented:\n\r");
+    if (err_is_fail(err)) return err;
+    err = shelly_write_str("- echo\n\r");
+    if (err_is_fail(err)) return err;
+    err = shelly_write_str("- run\n\r");
+    if (err_is_fail(err)) return err;
+    err = shelly_write_str("- ps\n\r");
+    if (err_is_fail(err)) return err;
+    err = shelly_write_str("- help\n\r");
+    if (err_is_fail(err)) return err;
+
+    return SYS_ERR_OK;
+}
+
 static errval_t shelly_cmd_echo(char * line) {
     errval_t err;
     err = shelly_write_str(line);
@@ -75,6 +91,8 @@ static errval_t handle_shelly_cmd(char* line, size_t len) {
         return shelly_cmd_run(remaining_line);
     } else if (strcmp(cmd, "ps") == 0) {
         return shelly_cmd_ps(remaining_line);
+    } else if (strcmp(cmd, "help") == 0) {
+        return shelly_cmd_help(remaining_line);
     } else {
         char buf[256];
         snprintf(buf, 256, "unknown command \"%s\"\n\r", cmd);