diff --git a/pkg/cli/gptscript.go b/pkg/cli/gptscript.go
index a8561abf..5a44c5fb 100644
--- a/pkg/cli/gptscript.go
+++ b/pkg/cli/gptscript.go
@@ -361,6 +361,11 @@ func (r *GPTScript) Run(cmd *cobra.Command, args []string) (retErr error) {
 				gptOpt.Env = append(gptOpt.Env, system.BinEnvVar+"="+system.Bin())
 			}
 
+			// If the DefaultModel is set, then pass the correct environment variable.
+			if r.DefaultModel != "" {
+				gptOpt.Env = append(gptOpt.Env, "GPTSCRIPT_SDKSERVER_DEFAULT_MODEL="+r.DefaultModel)
+			}
+
 			args = append([]string{args[0]}, "--file="+file)
 
 			if len(args) > 2 {