diff --git a/codex-rs/app-server-protocol/src/protocol.rs b/codex-rs/app-server-protocol/src/protocol.rs
index c32da0cdca..9a74eeba8c 100644
--- a/codex-rs/app-server-protocol/src/protocol.rs
+++ b/codex-rs/app-server-protocol/src/protocol.rs
@@ -1006,6 +1006,7 @@ mod tests {
             request_id: RequestId::Integer(42),
             params: NewConversationParams {
                 model: Some("gpt-5-codex".to_string()),
+                model_provider: None,
                 profile: None,
                 cwd: None,
                 approval_policy: Some(AskForApproval::OnRequest),