diff --git a/libflux/flux-core/src/bin/fluxdoc.rs b/libflux/flux-core/src/bin/fluxdoc.rs
index 4eb2caeb29..8c8e7094ef 100644
--- a/libflux/flux-core/src/bin/fluxdoc.rs
+++ b/libflux/flux-core/src/bin/fluxdoc.rs
@@ -301,7 +301,7 @@ impl<'a> example::Executor for CLIExecutor<'a> {
             .arg("csv")
             .arg(tmpfile.path())
             .arg("--feature")
-            .arg("labelPolymorphism");
+            .arg(r#"{"labelPolymorphism": true}"#);
         log::debug!("Executing {:?}", cmd);
         let output = cmd
             .output()