diff --git a/codex-rs/core/src/tools/spec_tests.rs b/codex-rs/core/src/tools/spec_tests.rs
index bab44764f0..6f0e7496b8 100644
--- a/codex-rs/core/src/tools/spec_tests.rs
+++ b/codex-rs/core/src/tools/spec_tests.rs
@@ -2090,12 +2090,12 @@ fn tool_suggest_can_be_registered_without_search_tool() {
     let ToolSpec::Function(ResponsesApiTool { description, .. }) = &tool_suggest.spec else {
         panic!("expected function tool");
     };
-    assert!(
-        description.contains(
-            "You've already tried to find a matching available tool for the user's request"
-        )
-    );
-    assert!(description.contains("This includes `tool_search` (if available) and other means."));
+    assert!(description.contains(
+        "Suggests a missing connector in an installed plugin, or in narrower cases a not installed but discoverable plugin"
+    ));
+    assert!(description.contains(
+        "You've already tried to find a matching available tool for the user's request but couldn't find a good match. This includes `tool_search` (if available) and other means."
+    ));
 }
 
 #[test]
@@ -2343,6 +2343,9 @@ fn tool_suggest_description_lists_discoverable_tools() {
     else {
         panic!("expected function tool");
     };
+    assert!(description.contains(
+        "Suggests a missing connector in an installed plugin, or in narrower cases a not installed but discoverable plugin"
+    ));
     assert!(description.contains("Google Calendar"));
     assert!(description.contains("Gmail"));
     assert!(description.contains("Sample Plugin"));
@@ -2355,10 +2358,21 @@ fn tool_suggest_description_lists_discoverable_tools() {
     );
     assert!(
         description.contains(
-            "You've already tried to find a matching available tool for the user's request"
+            "You've already tried to find a matching available tool for the user's request but couldn't find a good match. This includes `tool_search` (if available) and other means."
         )
     );
-    assert!(description.contains("This includes `tool_search` (if available) and other means."));
+    assert!(description.contains(
+        "For connectors/apps that are not installed but needed for an installed plugin, suggest to install them if the task requirements match precisely."
+    ));
+    assert!(description.contains(
+        "For plugins that are not installed but discoverable, only suggest discoverable and installable plugins when the user's intent very explicitly and unambiguously matches that plugin itself."
+    ));
+    assert!(description.contains(
+        "Do not suggest a plugin just because one of its connectors or capabilities seems relevant."
+    ));
+    assert!(description.contains(
+        "Apply the stricter explicit-and-unambiguous rule for *discoverable tools* like plugin install suggestions; *missing tools* like connector install suggestions continue to use the normal clear-fit standard."
+    ));
     assert!(description.contains("DO NOT explore or recommend tools that are not on this list."));
     assert!(!description.contains("tool_search fails to find a good match"));
     let JsonSchema::Object { required, .. } = parameters else {
diff --git a/codex-rs/core/templates/search_tool/tool_suggest_description.md b/codex-rs/core/templates/search_tool/tool_suggest_description.md
index 75e58958b5..ad0a50fcc1 100644
--- a/codex-rs/core/templates/search_tool/tool_suggest_description.md
+++ b/codex-rs/core/templates/search_tool/tool_suggest_description.md
@@ -1,10 +1,11 @@
 # Tool suggestion discovery
 
-Suggests a discoverable connector or plugin when the user clearly wants a capability that is not currently available in the active `tools` list.
+Suggests a missing connector in an installed plugin, or in narrower cases a not installed but discoverable plugin, when the user clearly wants a capability that is not currently available in the active `tools` list.
 
 Use this ONLY when:
 - You've already tried to find a matching available tool for the user's request but couldn't find a good match. This includes `tool_search` (if available) and other means.
-- AND the user's request strongly matches one of the discoverable tools listed below.
+- For connectors/apps that are not installed but needed for an installed plugin, suggest to install them if the task requirements match precisely.
+- For plugins that are not installed but discoverable, only suggest discoverable and installable plugins when the user's intent very explicitly and unambiguously matches that plugin itself. Do not suggest a plugin just because one of its connectors or capabilities seems relevant.
 
 Tool suggestions should only use the discoverable tools listed here. DO NOT explore or recommend tools that are not on this list.
 
@@ -14,7 +15,7 @@ Discoverable tools:
 Workflow:
 
 1. Ensure all possible means have been exhausted to find an existing available tool but none of them matches the request intent.
-2. Match the user's request against the discoverable tools list above.
+2. Match the user's request against the discoverable tools list above. Apply the stricter explicit-and-unambiguous rule for *discoverable tools* like plugin install suggestions; *missing tools* like connector install suggestions continue to use the normal clear-fit standard.
 3. If one tool clearly fits, call `tool_suggest` with:
    - `tool_type`: `connector` or `plugin`
    - `action_type`: `install` or `enable`