diff --git a/codex-rs/core/src/tools/handlers/request_plugin_install.rs b/codex-rs/core/src/tools/handlers/request_plugin_install.rs
index e44ed41fa4..c57df35fe5 100644
--- a/codex-rs/core/src/tools/handlers/request_plugin_install.rs
+++ b/codex-rs/core/src/tools/handlers/request_plugin_install.rs
@@ -79,7 +79,7 @@ impl ToolExecutor<ToolInvocation> for RequestPluginInstallHandler {
     }
 
     fn supports_parallel_tool_calls(&self) -> bool {
-        true
+        false
     }
 
     fn handle(&self, invocation: ToolInvocation) -> codex_tools::ToolExecutorFuture<'_> {
diff --git a/codex-rs/core/src/tools/handlers/request_plugin_install_tests.rs b/codex-rs/core/src/tools/handlers/request_plugin_install_tests.rs
index 93b761be58..774ed49116 100644
--- a/codex-rs/core/src/tools/handlers/request_plugin_install_tests.rs
+++ b/codex-rs/core/src/tools/handlers/request_plugin_install_tests.rs
@@ -21,6 +21,16 @@ use rmcp::model::ElicitationAction;
 use serde_json::json;
 use tempfile::tempdir;
 
+#[test]
+fn request_plugin_install_does_not_support_parallel_tool_calls() {
+    let handler = RequestPluginInstallHandler::new(
+        Vec::new(),
+        ToolSuggestPresentation::RecommendationContext,
+    );
+
+    assert!(!handler.supports_parallel_tool_calls());
+}
+
 #[tokio::test]
 async fn verified_plugin_install_completed_requires_installed_plugin() {
     let codex_home = tempdir().expect("tempdir should succeed");