diff --git a/projects/ucap-webmessenger-api/src/lib/apis/api.ts b/projects/ucap-webmessenger-api/src/lib/apis/api.ts
index 9aec892e..3deb590a 100644
--- a/projects/ucap-webmessenger-api/src/lib/apis/api.ts
+++ b/projects/ucap-webmessenger-api/src/lib/apis/api.ts
@@ -20,4 +20,6 @@ export type APIEncoder<REQ> = (
       [param: string]: string | string[];
     };
 
+export type APIFormDataEncoder<REQ> = (req: REQ) => FormData;
+
 export type APIDecoder<RES> = (res: any) => RES;