diff --git a/R/yaml_read_agent.R b/R/yaml_read_agent.R
index c00944d11..4816c4dad 100644
--- a/R/yaml_read_agent.R
+++ b/R/yaml_read_agent.R
@@ -562,6 +562,12 @@ make_validation_steps <- function(steps) {
       FUN = function(x) {
 
         step_i <- steps[[x]]
+
+        # Handle scalar steps (no arguments): `- rows_distinct` in YAML
+        if (is.character(step_i)) {
+          return(paste0("%>%\n", step_i, "()"))
+        }
+
         step_fn <- names(step_i)
 
         args <-
diff --git a/R/yaml_write.R b/R/yaml_write.R
index e8a43dde6..b09fae86f 100644
--- a/R/yaml_write.R
+++ b/R/yaml_write.R
@@ -181,9 +181,8 @@
 #'     columns: c(date, date_time)
 #' - col_vals_regex:
 #'     columns: c(b)
-#'     regex: '[0-9]-[a-z]{3}-[0-9]{3}'
-#' - rows_distinct:
-#'     columns: ~
+#'     pattern: '[0-9]-[a-z]{3}-[0-9]{3}'
+#' - rows_distinct
 #' - col_vals_gt:
 #'     columns: c(d)
 #'     value: 100.0
@@ -621,9 +620,8 @@ yaml_write <- function(
 #'     columns: vars(date_time)
 #' - col_vals_regex:
 #'     columns: vars(b)
-#'     regex: '[0-9]-[a-z]{3}-[0-9]{3}'
-#' - rows_distinct:
-#'     columns: ~
+#'     pattern: '[0-9]-[a-z]{3}-[0-9]{3}'
+#' - rows_distinct
 #' - col_vals_gt:
 #'     columns: vars(d)
 #'     value: 100.0
diff --git a/inst/yaml/agent-small_table.yml b/inst/yaml/agent-small_table.yml
index 90abf5670..9ef7ff8fa 100644
--- a/inst/yaml/agent-small_table.yml
+++ b/inst/yaml/agent-small_table.yml
@@ -16,8 +16,7 @@ steps:
 - col_vals_regex:
     columns: vars(b)
     pattern: '[0-9]-[a-z]{3}-[0-9]{3}'
-- rows_distinct:
-    columns: ~
+- rows_distinct
 - col_vals_gt:
     columns: vars(d)
     value: 100.0
diff --git a/vignettes/YAML.Rmd b/vignettes/YAML.Rmd
index 421f19c25..2510e0ece 100644
--- a/vignettes/YAML.Rmd
+++ b/vignettes/YAML.Rmd
@@ -170,8 +170,7 @@ steps:
       pattern: '^[0-9]-[a-z]{3}-[0-9]{3}$'
 
   # rows_distinct()
-  - rows_distinct:
-      columns: ~
+  - rows_distinct
 ```
 
 Arguments that use R expressions (like column selections via `vars()`) are stored as strings and evaluated when the YAML is read back.