diff --git a/sdk/ai/ai-projects/src/agents/index.ts b/sdk/ai/ai-projects/src/agents/index.ts
index 151c699ed3ba..f4bd155c943e 100644
--- a/sdk/ai/ai-projects/src/agents/index.ts
+++ b/sdk/ai/ai-projects/src/agents/index.ts
@@ -259,8 +259,7 @@ function getAgents(context: Client): AgentsOperations {
       listFiles(context, {...requestParams, body: {purpose } }),
     uploadFile: (content: ReadableStream | NodeJS.ReadableStream, purpose: string, fileName?: string, requestParams?: OptionalRequestParameters) =>
       uploadFile(context, {
-        body: [{ name: "file" as const, body: content, filename: fileName }],
-        queryParameters: { purpose },
+        body: [{ name: "file" as const, body: content, filename: fileName }, {name: "purpose" as const, body: purpose}],
         ...(requestParams as { [key: string]: any; }),
         contentType: "multipart/form-data"
       }),
diff --git a/sdk/ai/ai-projects/test/public/agents/files.spec.ts b/sdk/ai/ai-projects/test/public/agents/files.spec.ts
index c14abc1002a3..e26788832349 100644
--- a/sdk/ai/ai-projects/test/public/agents/files.spec.ts
+++ b/sdk/ai/ai-projects/test/public/agents/files.spec.ts
@@ -38,7 +38,7 @@ describe("Agents - files", () => {
         controller.close();
       }
     });
-    const file = await agents.uploadFile(fileContent, "purpose", "fileName");
+    const file = await agents.uploadFile(fileContent, "assistants", "fileName");
     assert.isNotEmpty(file);
   });
 
@@ -49,7 +49,7 @@ describe("Agents - files", () => {
         controller.close();
       }
     });
-    const file = await agents.uploadFile(fileContent, "purpose", "fileName");
+    const file = await agents.uploadFile(fileContent, "assistants", "fileName");
     const deleted = await agents.deleteFile(file.id);
     assert.isNotNull(deleted);
   });
@@ -61,7 +61,7 @@ describe("Agents - files", () => {
         controller.close();
       }
     });
-    const file = await agents.uploadFile(fileContent, "purpose", "fileName");
+    const file = await agents.uploadFile(fileContent, "assistants", "fileName");
     const _file = await agents.getFile(file.id);
     assert.isNotEmpty(_file);
     assert.equal(_file.id, file.id);
@@ -75,7 +75,7 @@ describe("Agents - files", () => {
         controller.close();
       }
     });
-    const file = await agents.uploadFile(fileContent, "purpose", "fileName");
+    const file = await agents.uploadFile(fileContent, "assistants", "fileName");
     const content = await agents.getFileContent(file.id);
     assert.isNotEmpty(content);
   });