diff --git a/website/src/lib/oasst_api_client.ts b/website/src/lib/oasst_api_client.ts
index 45a0859e..b0caf3c6 100644
--- a/website/src/lib/oasst_api_client.ts
+++ b/website/src/lib/oasst_api_client.ts
@@ -61,4 +61,27 @@ export default class OasstApiClient {
       message_id: messageId,
     });
   }
+
+  // TODO return a strongly typed Task?
+  // This method is used to record interaction with task while fetching next task.
+  // This is a raw Json type, so we can't use it to strongly type the task.
+  async interactTask(
+    updateType: string,
+    messageId: string,
+    userMessageId: string,
+    content: object,
+    userToken: JWT
+  ): Promise<any> {
+    return this.post("/api/v1/tasks/interaction", {
+      type: updateType,
+      user: {
+        id: userToken.sub,
+        display_name: userToken.name || userToken.email,
+        auth_method: "local",
+      },
+      message_id: messageId,
+      user_message_id: userMessageId,
+      ...content,
+    });
+  }
 }
diff --git a/website/src/pages/api/update_task.ts b/website/src/pages/api/update_task.ts
index 2d371354..fbc8da18 100644
--- a/website/src/pages/api/update_task.ts
+++ b/website/src/pages/api/update_task.ts
@@ -1,4 +1,5 @@
 import { getToken } from "next-auth/jwt";
+import OasstApiClient from "src/lib/oasst_api_client";
 import prisma from "src/lib/prismadb";
 
 /**
@@ -18,6 +19,8 @@ const handler = async (req, res) => {
     return;
   }
 
+  const oasstApiClient = new OasstApiClient(process.env.FASTAPI_URL, process.env.FASTAPI_KEY);
+
   // Parse out the local task ID and the interaction contents.
   const { id, content, update_type } = await JSON.parse(req.body);
 
@@ -34,28 +37,7 @@ const handler = async (req, res) => {
     },
   });
 
-  // Send the interaction to the Task Backend.  This automatically fetches the
-  // next task in the sequence (or the done task).
-  // TODO(#353): Move this into OasstApiClient.
-  const interactionRes = await fetch(`${process.env.FASTAPI_URL}/api/v1/tasks/interaction`, {
-    method: "POST",
-    headers: {
-      "X-API-Key": process.env.FASTAPI_KEY,
-      "Content-Type": "application/json",
-    },
-    body: JSON.stringify({
-      type: update_type,
-      user: {
-        id: token.sub,
-        display_name: token.name || token.email,
-        auth_method: "local",
-      },
-      message_id: id,
-      user_message_id: interaction.id,
-      ...content,
-    }),
-  });
-  const newTask = await interactionRes.json();
+  const newTask = await oasstApiClient.interactTask(update_type, id, interaction.id, content, token);
 
   // Stores the new task with our database.
   const newRegisteredTask = await prisma.registeredTask.create({