tensorzero · shuyangli · Dec 17, 2025 · Dec 16, 2025
diff --git a/gateway/src/routes/internal.rs b/gateway/src/routes/internal.rs
@@ -95,6 +95,10 @@ pub fn build_internal_non_otel_enabled_routes() -> Router<AppStateData> {
             "/internal/evaluations/run-stats",
             get(endpoints::internal::evaluations::get_evaluation_run_stats_handler),
         )
+        .route(
+            "/internal/evaluations/datapoint-count",
+            get(endpoints::internal::evaluations::count_datapoints_handler),
+        )
         .route(
             "/internal/evaluations/runs",
             get(endpoints::internal::evaluations::list_evaluation_runs_handler),
@@ -105,8 +109,10 @@ pub fn build_internal_non_otel_enabled_routes() -> Router<AppStateData> {
             get(endpoints::workflow_evaluations::internal::get_workflow_evaluation_projects_handler),
         )
         .route(
-            "/internal/evaluations/datapoint-count",
-            get(endpoints::internal::evaluations::count_datapoints_handler),
+            "/internal/workflow-evaluations/projects/count",
+            get(
+                endpoints::workflow_evaluations::internal::get_workflow_evaluation_project_count_handler,
+            ),
         )
         .route(
             "/internal/models/usage",

diff --git a/internal/tensorzero-node/lib/bindings/GetWorkflowEvaluationProjectCountResponse.ts b/internal/tensorzero-node/lib/bindings/GetWorkflowEvaluationProjectCountResponse.ts
@@ -0,0 +1,6 @@
+// This file was generated by [ts-rs](https://github.com/Aleph-Alpha/ts-rs). Do not edit this file manually.
+
+/**
+ * Response containing the count of workflow evaluation projects.
+ */
+export type GetWorkflowEvaluationProjectCountResponse = { count: number };
diff --git a/internal/tensorzero-node/lib/bindings/index.ts b/internal/tensorzero-node/lib/bindings/index.ts
@@ -123,6 +123,7 @@ export * from "./GetInferencesResponse";
 export * from "./GetModelInferencesResponse";
 export * from "./GetModelLatencyResponse";
 export * from "./GetModelUsageResponse";
+export * from "./GetWorkflowEvaluationProjectCountResponse";
 export * from "./GetWorkflowEvaluationProjectsResponse";
 export * from "./GoogleAIStudioGeminiProvider";
 export * from "./GroqProvider";

diff --git a/tensorzero-core/src/db/clickhouse/workflow_evaluation_queries.rs b/tensorzero-core/src/db/clickhouse/workflow_evaluation_queries.rs
@@ -5,10 +5,10 @@ use std::collections::HashMap;
 use async_trait::async_trait;
 
 use super::ClickHouseConnectionInfo;
-use super::select_queries::parse_json_rows;
+use super::select_queries::{parse_count, parse_json_rows};
 use crate::db::workflow_evaluation_queries::WorkflowEvaluationProjectRow;
 use crate::db::workflow_evaluation_queries::WorkflowEvaluationQueries;
-use crate::error::Error;
+use crate::error::{Error, ErrorDetails};
 
 #[async_trait]
 impl WorkflowEvaluationQueries for ClickHouseConnectionInfo {
@@ -41,6 +41,26 @@ impl WorkflowEvaluationQueries for ClickHouseConnectionInfo {
 
         parse_json_rows(response.response.as_str())
     }
+
+    async fn count_workflow_evaluation_projects(&self) -> Result<u32, Error> {
+        let query = r"
+            SELECT
+                toUInt32(countDistinct(project_name)) as count
+            FROM DynamicEvaluationRunByProjectName
+            WHERE project_name IS NOT NULL
+            FORMAT JSONEachRow
+        "
+        .to_string();
+
+        let response = self.run_query_synchronous_no_params(query).await?;
+        let count = parse_count(response.response.as_str())?;
+
+        u32::try_from(count).map_err(|error| {
+            Error::new(ErrorDetails::ClickHouseDeserialization {
+                message: format!("Failed to convert workflow evaluation project count: {error}"),
+            })
+        })
+    }
 }
 
 #[cfg(test)]
@@ -160,4 +180,39 @@ mod tests {
         assert_eq!(result[1].name, "project2");
         assert_eq!(result[2].name, "project3");
     }
+
+    #[tokio::test]
+    async fn test_count_workflow_evaluation_projects() {
+        let mut mock_clickhouse_client = MockClickHouseClient::new();
+
+        mock_clickhouse_client
+            .expect_run_query_synchronous()
+            .withf(|query, params| {
+                assert_query_contains(
+                    query,
+                    "
+                SELECT toUInt32(countDistinct(project_name)) as count
+                FROM DynamicEvaluationRunByProjectName
+                WHERE project_name IS NOT NULL
+                FORMAT JSONEachRow",
+                );
+                assert!(params.is_empty());
+                true
+            })
+            .returning(|_, _| {
+                Ok(ClickHouseResponse {
+                    response: r#"{"count":2}"#.to_string(),
+                    metadata: ClickHouseResponseMetadata {
+                        read_rows: 1,
+                        written_rows: 0,
+                    },
+                })
+            });
+
+        let conn = ClickHouseConnectionInfo::new_mock(Arc::new(mock_clickhouse_client));
+
+        let count = conn.count_workflow_evaluation_projects().await.unwrap();
+
+        assert_eq!(count, 2);
+    }
 }
diff --git a/tensorzero-core/src/db/workflow_evaluation_queries.rs b/tensorzero-core/src/db/workflow_evaluation_queries.rs
@@ -27,4 +27,7 @@ pub trait WorkflowEvaluationQueries {
         limit: u32,
         offset: u32,
     ) -> Result<Vec<WorkflowEvaluationProjectRow>, Error>;
+
+    /// Counts workflow evaluation projects.
+    async fn count_workflow_evaluation_projects(&self) -> Result<u32, Error>;
 }
diff --git a/tensorzero-core/src/endpoints/workflow_evaluations/internal/get_project_count.rs b/tensorzero-core/src/endpoints/workflow_evaluations/internal/get_project_count.rs
@@ -0,0 +1,51 @@
+//! Handler for getting the workflow evaluation project count.
+
+use axum::Json;
+use axum::extract::State;
+use tracing::instrument;
+
+use super::types::GetWorkflowEvaluationProjectCountResponse;
+use crate::db::workflow_evaluation_queries::WorkflowEvaluationQueries;
+use crate::error::Error;
+use crate::utils::gateway::{AppState, AppStateData};
+
+/// Handler for `GET /internal/workflow-evaluations/projects/count`
+#[axum::debug_handler(state = AppStateData)]
+#[instrument(name = "workflow_evaluations.count_projects", skip_all)]
+pub async fn get_workflow_evaluation_project_count_handler(
+    State(app_state): AppState,
+) -> Result<Json<GetWorkflowEvaluationProjectCountResponse>, Error> {
+    let response =
+        get_workflow_evaluation_project_count(&app_state.clickhouse_connection_info).await?;
+
+    Ok(Json(response))
+}
+
+/// Core business logic for retrieving the workflow evaluation project count.
+pub async fn get_workflow_evaluation_project_count(
+    clickhouse: &impl WorkflowEvaluationQueries,
+) -> Result<GetWorkflowEvaluationProjectCountResponse, Error> {
+    let count = clickhouse.count_workflow_evaluation_projects().await?;
+    Ok(GetWorkflowEvaluationProjectCountResponse { count })
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::db::workflow_evaluation_queries::MockWorkflowEvaluationQueries;
+
+    #[tokio::test]
+    async fn test_get_workflow_evaluation_project_count() {
+        let mut mock_clickhouse = MockWorkflowEvaluationQueries::new();
+        mock_clickhouse
+            .expect_count_workflow_evaluation_projects()
+            .times(1)
+            .returning(|| Box::pin(async move { Ok(7) }));
+
+        let response = get_workflow_evaluation_project_count(&mock_clickhouse)
+            .await
+            .unwrap();
+
+        assert_eq!(response.count, 7);
+    }
+}
diff --git a/tensorzero-core/src/endpoints/workflow_evaluations/internal/get_projects.rs b/tensorzero-core/src/endpoints/workflow_evaluations/internal/get_projects.rs
@@ -2,16 +2,24 @@
 
 use axum::Json;
 use axum::extract::{Query, State};
+use serde::Deserialize;
 use tracing::instrument;
 
-use super::types::{
-    GetWorkflowEvaluationProjectsParams, GetWorkflowEvaluationProjectsResponse,
-    WorkflowEvaluationProject,
-};
+use super::types::{GetWorkflowEvaluationProjectsResponse, WorkflowEvaluationProject};
 use crate::db::workflow_evaluation_queries::WorkflowEvaluationQueries;
 use crate::error::Error;
 use crate::utils::gateway::{AppState, AppStateData};
 
+/// Query parameters for getting workflow evaluation projects.
+#[derive(Debug, Deserialize)]
+pub struct GetWorkflowEvaluationProjectsParams {
+    pub limit: Option<u32>,
+    pub offset: Option<u32>,
+}
+
+const DEFAULT_GET_WORKFLOW_EVALUATION_PROJECTS_LIMIT: u32 = 100;
+const DEFAULT_GET_WORKFLOW_EVALUATION_PROJECTS_OFFSET: u32 = 0;
+
 /// Handler for `GET /internal/workflow-evaluations/projects`
 ///
 /// Returns a paginated list of workflow evaluation projects.
@@ -23,8 +31,12 @@ pub async fn get_workflow_evaluation_projects_handler(
 ) -> Result<Json<GetWorkflowEvaluationProjectsResponse>, Error> {
     let response = get_workflow_evaluation_projects(
         &app_state.clickhouse_connection_info,
-        params.limit,
-        params.offset,
+        params
+            .limit
+            .unwrap_or(DEFAULT_GET_WORKFLOW_EVALUATION_PROJECTS_LIMIT),
+        params
+            .offset
+            .unwrap_or(DEFAULT_GET_WORKFLOW_EVALUATION_PROJECTS_OFFSET),
     )
     .await?;
 

diff --git a/tensorzero-core/src/endpoints/workflow_evaluations/internal/mod.rs b/tensorzero-core/src/endpoints/workflow_evaluations/internal/mod.rs
@@ -2,8 +2,11 @@
 //!
 //! These endpoints support the UI for viewing and managing workflow evaluation runs and results.
 
+mod get_project_count;
 mod get_projects;
 mod types;
 
+pub use get_project_count::get_workflow_evaluation_project_count;
+pub use get_project_count::get_workflow_evaluation_project_count_handler;
 pub use get_projects::get_workflow_evaluation_projects_handler;
 pub use types::*;
diff --git a/tensorzero-core/src/endpoints/workflow_evaluations/internal/types.rs b/tensorzero-core/src/endpoints/workflow_evaluations/internal/types.rs
@@ -7,19 +7,6 @@ use serde::{Deserialize, Serialize};
 // Get Workflow Evaluation Projects
 // =============================================================================
 
-/// Query parameters for getting workflow evaluation projects.
-#[derive(Debug, Deserialize)]
-pub struct GetWorkflowEvaluationProjectsParams {
-    #[serde(default = "default_limit")]
-    pub limit: u32,
-    #[serde(default)]
-    pub offset: u32,
-}
-
-fn default_limit() -> u32 {
-    100
-}
-
 /// Response containing a list of workflow evaluation projects.
 #[derive(Debug, Serialize, Deserialize, ts_rs::TS)]
 #[ts(export)]
@@ -35,3 +22,14 @@ pub struct WorkflowEvaluationProject {
     pub count: u32,
     pub last_updated: DateTime<Utc>,
 }
+
+// =============================================================================
+// Get Workflow Evaluation Project Count
+// =============================================================================
+
+/// Response containing the count of workflow evaluation projects.
+#[derive(Debug, Serialize, Deserialize, ts_rs::TS)]
+#[ts(export)]
+pub struct GetWorkflowEvaluationProjectCountResponse {
+    pub count: u32,
+}
diff --git a/tensorzero-core/tests/e2e/db/workflow_evaluation_queries.rs b/tensorzero-core/tests/e2e/db/workflow_evaluation_queries.rs
@@ -38,3 +38,19 @@ async fn test_list_workflow_evaluation_projects_with_fixture_data() {
         "Expected at least one of the fixture projects to be present. Found: {project_names:?}",
     );
 }
+
+/// Ensures workflow evaluation project counts are returned from ClickHouse.
+#[tokio::test]
+async fn test_count_workflow_evaluation_projects_with_fixture_data() {
+    let clickhouse = get_clickhouse().await;
+
+    let result = clickhouse
+        .count_workflow_evaluation_projects()
+        .await
+        .unwrap();
+
+    assert!(
+        result >= 2,
+        "Expected at least 2 workflow evaluation projects from fixtures, got {result}",
+    );
+}
diff --git a/tensorzero-core/tests/e2e/endpoints/internal/workflow_evaluations.rs b/tensorzero-core/tests/e2e/endpoints/internal/workflow_evaluations.rs
@@ -1,7 +1,9 @@
 //! E2E tests for the workflow evaluation endpoints.
 
 use reqwest::Client;
-use tensorzero_core::endpoints::workflow_evaluations::internal::GetWorkflowEvaluationProjectsResponse;
+use tensorzero_core::endpoints::workflow_evaluations::internal::{
+    GetWorkflowEvaluationProjectCountResponse, GetWorkflowEvaluationProjectsResponse,
+};
 
 use crate::common::get_gateway_endpoint;
 
@@ -58,3 +60,23 @@ async fn test_get_workflow_evaluation_projects_with_pagination() {
         response.projects.len()
     );
 }
+
+#[tokio::test(flavor = "multi_thread")]
+async fn test_get_workflow_evaluation_project_count_endpoint() {
+    let http_client = Client::new();
+    let url = get_gateway_endpoint("/internal/workflow-evaluations/projects/count");
+
+    let resp = http_client.get(url).send().await.unwrap();
+    assert!(
+        resp.status().is_success(),
+        "get_workflow_evaluation_project_count request failed: status={:?}",
+        resp.status()
+    );
+
+    let response: GetWorkflowEvaluationProjectCountResponse = resp.json().await.unwrap();
+
+    assert!(
+        response.count > 0,
+        "Expected workflow evaluation project count to be greater than 0"
+    );
+}
diff --git a/ui/app/routes/index.tsx b/ui/app/routes/index.tsx
@@ -22,10 +22,7 @@ import {
 import { countInferencesByFunction } from "~/utils/clickhouse/inference.server";
 import { getConfig, getAllFunctionConfigs } from "~/utils/config/index.server";
 import type { Route } from "./+types/index";
-import {
-  countWorkflowEvaluationProjects,
-  countWorkflowEvaluationRuns,
-} from "~/utils/clickhouse/workflow_evaluations.server";
+import { countWorkflowEvaluationRuns } from "~/utils/clickhouse/workflow_evaluations.server";
 import { getTensorZeroClient } from "~/utils/tensorzero.server";
 
 export const handle: RouteHandle = {
@@ -111,7 +108,7 @@ export async function loader() {
   const numEvaluationRunsPromise = httpClient.countEvaluationRuns();
   const numWorkflowEvaluationRunsPromise = countWorkflowEvaluationRuns();
   const numWorkflowEvaluationRunProjectsPromise =
-    countWorkflowEvaluationProjects();
+    httpClient.countWorkflowEvaluationProjects();
   const configPromise = getConfig();
   const functionConfigsPromise = getAllFunctionConfigs();
   const numModelsUsedPromise = httpClient

diff --git a/ui/app/routes/workflow_evaluations/route.tsx b/ui/app/routes/workflow_evaluations/route.tsx
@@ -10,7 +10,6 @@ import {
 import {
   getWorkflowEvaluationRuns,
   countWorkflowEvaluationRuns,
-  countWorkflowEvaluationProjects,
 } from "~/utils/clickhouse/workflow_evaluations.server";
 import WorkflowEvaluationRunsTable from "./WorkflowEvaluationRunsTable";
 import WorkflowEvaluationProjectsTable from "./WorkflowEvaluationProjectsTable";
@@ -24,6 +23,7 @@ export async function loader({ request }: Route.LoaderArgs) {
   const runLimit = parseInt(searchParams.get("runLimit") || "15");
   const projectOffset = parseInt(searchParams.get("projectOffset") || "0");
   const projectLimit = parseInt(searchParams.get("projectLimit") || "15");
+  const tensorZeroClient = getTensorZeroClient();
   const [
     workflowEvaluationRuns,
     count,
@@ -32,11 +32,8 @@ export async function loader({ request }: Route.LoaderArgs) {
   ] = await Promise.all([
     getWorkflowEvaluationRuns(runLimit, runOffset),
     countWorkflowEvaluationRuns(),
-    getTensorZeroClient().getWorkflowEvaluationProjects(
-      projectLimit,
-      projectOffset,
-    ),
-    countWorkflowEvaluationProjects(),
+    tensorZeroClient.getWorkflowEvaluationProjects(projectLimit, projectOffset),
+    tensorZeroClient.countWorkflowEvaluationProjects(),
   ]);
   const workflowEvaluationProjects =
     workflowEvaluationProjectsResponse.projects;

diff --git a/ui/app/utils/clickhouse/workflow_evaluations.server.ts b/ui/app/utils/clickhouse/workflow_evaluations.server.ts
@@ -315,21 +315,6 @@ export async function countWorkflowEvaluationRunEpisodes(
   return rows[0].count;
 }
 
-export async function countWorkflowEvaluationProjects(): Promise<number> {
-  const query = `
-  SELECT toUInt32(countDistinct(project_name)) AS count
-  FROM DynamicEvaluationRunByProjectName
-  WHERE project_name IS NOT NULL
-`;
-  const result = await getClickhouseClient().query({
-    query,
-    format: "JSONEachRow",
-  });
-  const rows = await result.json<{ count: number }[]>();
-  const parsedRows = rows.map((row) => CountSchema.parse(row));
-  return parsedRows[0].count;
-}
-
 export async function searchWorkflowEvaluationRuns(
   limit: number,
   offset: number,