diff --git a/pageserver/client/src/mgmt_api.rs b/pageserver/client/src/mgmt_api.rs
index f68e323477..f53b3eaab2 100644
--- a/pageserver/client/src/mgmt_api.rs
+++ b/pageserver/client/src/mgmt_api.rs
@@ -1,4 +1,4 @@
-use pageserver_api::models::*;
+use pageserver_api::{models::*, shard::TenantShardId};
 use reqwest::{IntoUrl, Method};
 use utils::{
     http::error::HttpErrorBody,
@@ -68,9 +68,9 @@ impl Client {
 
     pub async fn tenant_details(
         &self,
-        tenant_id: TenantId,
+        tenant_shard_id: TenantShardId,
     ) -> Result<pageserver_api::models::TenantDetails> {
-        let uri = format!("{}/v1/tenant/{tenant_id}", self.mgmt_api_endpoint);
+        let uri = format!("{}/v1/tenant/{tenant_shard_id}", self.mgmt_api_endpoint);
         self.get(uri)
             .await?
             .json()
@@ -80,9 +80,12 @@ impl Client {
 
     pub async fn list_timelines(
         &self,
-        tenant_id: TenantId,
+        tenant_shard_id: TenantShardId,
     ) -> Result<Vec<pageserver_api::models::TimelineInfo>> {
-        let uri = format!("{}/v1/tenant/{tenant_id}/timeline", self.mgmt_api_endpoint);
+        let uri = format!(
+            "{}/v1/tenant/{tenant_shard_id}/timeline",
+            self.mgmt_api_endpoint
+        );
         self.get(&uri)
             .await?
             .json()
@@ -166,7 +169,7 @@ impl Client {
 
     pub async fn location_config(
         &self,
-        tenant_id: TenantId,
+        tenant_shard_id: TenantShardId,
         config: LocationConfig,
         flush_ms: Option<std::time::Duration>,
     ) -> Result<()> {
@@ -176,7 +179,7 @@ impl Client {
         };
         let path = format!(
             "{}/v1/tenant/{}/location_config",
-            self.mgmt_api_endpoint, tenant_id
+            self.mgmt_api_endpoint, tenant_shard_id
         );
         let path = if let Some(flush_ms) = flush_ms {
             format!("{}?flush_ms={}", path, flush_ms.as_millis())
@@ -202,4 +205,19 @@ impl Client {
             .await
             .map_err(Error::ReceiveBody)
     }
+
+    pub async fn tenant_synthetic_size(
+        &self,
+        tenant_shard_id: TenantShardId,
+    ) -> Result<TenantHistorySize> {
+        let uri = format!(
+            "{}/v1/tenant/{}/synthetic_size",
+            self.mgmt_api_endpoint, tenant_shard_id
+        );
+        self.get(&uri)
+            .await?
+            .json()
+            .await
+            .map_err(Error::ReceiveBody)
+    }
 }
diff --git a/pageserver/client/src/mgmt_api/util.rs b/pageserver/client/src/mgmt_api/util.rs
index 048a3bb7cd..bd85506d10 100644
--- a/pageserver/client/src/mgmt_api/util.rs
+++ b/pageserver/client/src/mgmt_api/util.rs
@@ -2,6 +2,7 @@
 
 use std::sync::Arc;
 
+use pageserver_api::shard::TenantShardId;
 use tokio::task::JoinSet;
 use utils::id::{TenantId, TenantTimelineId};
 
@@ -31,7 +32,10 @@ pub async fn get_pageserver_tenant_timelines_unsharded(
             async move {
                 (
                     tenant_id,
-                    mgmt_api_client.tenant_details(tenant_id).await.unwrap(),
+                    mgmt_api_client
+                        .tenant_details(TenantShardId::unsharded(tenant_id))
+                        .await
+                        .unwrap(),
                 )
             }
         });