diff --git a/server/config/feature_flag_configs/autopush.json b/server/config/feature_flag_configs/autopush.json
index fb01bc93ee..f6cd89499b 100644
--- a/server/config/feature_flag_configs/autopush.json
+++ b/server/config/feature_flag_configs/autopush.json
@@ -29,6 +29,12 @@
     "owner": "shixiao",
     "description": "Enables Gemini 3 Flash for NL detection."
   },
+  {
+    "name": "enable_gemini_3_5_flash",
+    "enabled": false,
+    "owner": "shixiao",
+    "description": "Enables Gemini 3.5 Flash for NL detection."
+  },
   {
     "name": "enable_nl_agent_detector",
     "enabled": true,
diff --git a/server/config/feature_flag_configs/custom.json b/server/config/feature_flag_configs/custom.json
index 6892cb71c9..6a64fe376a 100644
--- a/server/config/feature_flag_configs/custom.json
+++ b/server/config/feature_flag_configs/custom.json
@@ -29,6 +29,12 @@
     "owner": "shixiao",
     "description": "Enables Gemini 3 Flash for NL detection."
   },
+  {
+    "name": "enable_gemini_3_5_flash",
+    "enabled": false,
+    "owner": "shixiao",
+    "description": "Enables Gemini 3.5 Flash for NL detection."
+  },
   {
     "name": "enable_nl_agent_detector",
     "enabled": false,
diff --git a/server/config/feature_flag_configs/dev.json b/server/config/feature_flag_configs/dev.json
index 2e706f9164..e9fbdf6343 100644
--- a/server/config/feature_flag_configs/dev.json
+++ b/server/config/feature_flag_configs/dev.json
@@ -29,6 +29,12 @@
     "owner": "shixiao",
     "description": "Enables Gemini 3 Flash for NL detection."
   },
+  {
+    "name": "enable_gemini_3_5_flash",
+    "enabled": false,
+    "owner": "shixiao",
+    "description": "Enables Gemini 3.5 Flash for NL detection."
+  },
   {
     "name": "enable_nl_agent_detector",
     "enabled": false,
diff --git a/server/config/feature_flag_configs/local.json b/server/config/feature_flag_configs/local.json
index 5a35c5bc9b..affc158fdf 100644
--- a/server/config/feature_flag_configs/local.json
+++ b/server/config/feature_flag_configs/local.json
@@ -29,6 +29,12 @@
     "owner": "shixiao",
     "description": "Enables Gemini 3 Flash for NL detection."
   },
+  {
+    "name": "enable_gemini_3_5_flash",
+    "enabled": false,
+    "owner": "shixiao",
+    "description": "Enables Gemini 3.5 Flash for NL detection."
+  },
   {
     "name": "enable_nl_agent_detector",
     "enabled": true,
diff --git a/server/config/feature_flag_configs/staging.json b/server/config/feature_flag_configs/staging.json
index e27a0a1969..5fc0b5db0a 100644
--- a/server/config/feature_flag_configs/staging.json
+++ b/server/config/feature_flag_configs/staging.json
@@ -29,6 +29,12 @@
     "owner": "shixiao",
     "description": "Enables Gemini 3 Flash for NL detection."
   },
+  {
+    "name": "enable_gemini_3_5_flash",
+    "enabled": false,
+    "owner": "shixiao",
+    "description": "Enables Gemini 3.5 Flash for NL detection."
+  },
   {
     "name": "enable_nl_agent_detector",
     "enabled": false,