diff --git a/codex-rs/utils/plugins/src/plugin_namespace.rs b/codex-rs/utils/plugins/src/plugin_namespace.rs
index a485ab0013ca..db1b9ce5328b 100644
--- a/codex-rs/utils/plugins/src/plugin_namespace.rs
+++ b/codex-rs/utils/plugins/src/plugin_namespace.rs
@@ -39,28 +39,27 @@ pub fn agent_plugin_schema_status(contents: &str) -> AgentPluginSchemaStatus {
 
 pub fn find_plugin_manifest_path(plugin_root: &Path) -> Option<PathBuf> {
     let agent_manifest_path = plugin_root.join(AGENT_PLUGIN_MANIFEST_RELATIVE_PATH);
-    match std::fs::symlink_metadata(&agent_manifest_path) {
+    let agent_plugin_manifest = match std::fs::symlink_metadata(&agent_manifest_path) {
         Ok(metadata) if metadata.file_type().is_symlink() || !metadata.file_type().is_file() => {
             return None;
         }
-        Ok(_) => {
-            if std::fs::read_to_string(&agent_manifest_path)
-                .ok()
-                .is_some_and(|contents| {
-                    agent_plugin_schema_status(&contents) != AgentPluginSchemaStatus::Unrelated
-                })
-            {
-                return Some(agent_manifest_path);
-            }
-        }
-        Err(err) if err.kind() == std::io::ErrorKind::NotFound => {}
+        Ok(_) => std::fs::read_to_string(&agent_manifest_path)
+            .ok()
+            .is_some_and(|contents| {
+                agent_plugin_schema_status(&contents) != AgentPluginSchemaStatus::Unrelated
+            })
+            .then_some(agent_manifest_path),
+        Err(err) if err.kind() == std::io::ErrorKind::NotFound => None,
         Err(_) => return None,
-    }
+    };
 
+    // Prefer a Codex-side manifest over the Agent Plugin spec: the spec can't yet
+    // forward env vars to MCP servers (openai/codex#38438). Revert at parity.
     DISCOVERABLE_PLUGIN_MANIFEST_PATHS
         .iter()
         .map(|relative_path| plugin_root.join(relative_path))
         .find(|manifest_path| manifest_path.is_file())
+        .or(agent_plugin_manifest)
 }
 
 #[derive(serde::Deserialize)]
@@ -203,6 +202,22 @@ mod tests {
         assert_eq!(find_plugin_manifest_path(&plugin_root), Some(manifest_path));
     }
 
+    #[test]
+    fn prefers_codex_plugin_over_schema_declared_root_manifest() {
+        let tmp = tempdir().expect("tempdir");
+        let plugin_root = tmp.path().join("plugins/portable");
+        let codex_path = plugin_root.join(".codex-plugin/plugin.json");
+        fs::create_dir_all(codex_path.parent().expect("parent")).expect("mkdir");
+        fs::write(
+            plugin_root.join(AGENT_PLUGIN_MANIFEST_RELATIVE_PATH),
+            format!(r#"{{"$schema":"{AGENT_PLUGIN_SCHEMA_URI}","name":"portable"}}"#),
+        )
+        .expect("write spec manifest");
+        fs::write(&codex_path, r#"{"name":"portable"}"#).expect("write codex manifest");
+
+        assert_eq!(find_plugin_manifest_path(&plugin_root), Some(codex_path));
+    }
+
     #[test]
     fn ignores_unrelated_root_plugin_manifest_before_legacy_fallback() {
         let tmp = tempdir().expect("tempdir");