Handling Errors at the Application Boundary in TypeScript

 export const signIn = os
   .input(SignInInput)
   .output(SignInOutput)
   .handler(async ({ input, context }) => {
     const headers = (context as { headers?: Headers }).headers;

     try {
       const result = await Effect.runPromise(
         Effect.gen(function* () {
           const auth = yield* AuthService;
           return yield* auth.signIn(input.email, input.password, headers);
         }).pipe(Effect.provide(AuthService.layer))
       );

       return {
         token: result.token,
         user: {
           id: result.user.id,
           name: result.user.name,
           // ... map other fields
         },
       };
     } catch (error) {
       const e = error as { _tag?: string; message?: string };

       if (e._tag === "InvalidCredentialsError") {
         throw new ORPCError("UNAUTHORIZED", { message: e.message });
       }
       if (e._tag === "AuthApiError") {
         throw new ORPCError("INTERNAL_SERVER_ERROR", { message: e.message });
       }
       throw error;
     }
   });