diff --git a/committer/src/api.rs b/committer/src/api.rs
index cab1c336..ded12abb 100644
--- a/committer/src/api.rs
+++ b/committer/src/api.rs
@@ -91,7 +91,7 @@ async fn metrics(registry: web::Data<Arc<Registry>>) -> impl Responder {
 }
 
 #[derive(Deserialize)]
-#[serde(tag = "variant", content = "value")]
+#[serde(rename_all = "lowercase", tag = "variant", content = "value")]
 enum HeightVariant {
     Latest,
     Height(u32),
@@ -99,7 +99,7 @@ enum HeightVariant {
 
 #[derive(Deserialize)]
 struct CostQueryParams {
-    from_height: HeightVariant,
+    variant: HeightVariant,
     limit: Option<usize>,
 }
 
@@ -110,7 +110,7 @@ async fn costs(
 ) -> impl Responder {
     let limit = query.limit.unwrap_or(100);
 
-    let response = match query.from_height {
+    let response = match query.variant {
         HeightVariant::Latest => data.get_latest_costs(limit).await,
         HeightVariant::Height(from_height) => data.get_costs(from_height, limit).await,
     };