diff --git a/codex-rs/core/src/guardian/mod.rs b/codex-rs/core/src/guardian/mod.rs
index 0984e5b022..4987348595 100644
--- a/codex-rs/core/src/guardian/mod.rs
+++ b/codex-rs/core/src/guardian/mod.rs
@@ -54,7 +54,7 @@ const GUARDIAN_MAX_MESSAGE_TRANSCRIPT_TOKENS: usize = 10_000;
 const GUARDIAN_MAX_TOOL_TRANSCRIPT_TOKENS: usize = 10_000;
 const GUARDIAN_MAX_MESSAGE_ENTRY_TOKENS: usize = 2_000;
 const GUARDIAN_MAX_TOOL_ENTRY_TOKENS: usize = 1_000;
-const GUARDIAN_MAX_ACTION_STRING_TOKENS: usize = 16_000;
+const GUARDIAN_MAX_ACTION_STRING_TOKENS: usize = 10_000;
 const GUARDIAN_RECENT_ENTRY_LIMIT: usize = 40;
 const TRUNCATION_TAG: &str = "truncated";
 
diff --git a/codex-rs/core/src/guardian/tests.rs b/codex-rs/core/src/guardian/tests.rs
index bab1038358..9888a9007c 100644
--- a/codex-rs/core/src/guardian/tests.rs
+++ b/codex-rs/core/src/guardian/tests.rs
@@ -827,6 +827,10 @@ fn format_guardian_action_pretty_truncates_large_string_fields() -> serde_json::
     assert!(rendered.text.contains("\"tool\": \"apply_patch\""));
     assert!(rendered.text.contains("<truncated omitted_approx_tokens="));
     assert!(rendered.text.len() < patch.len());
+    assert!(
+        rendered.text.len() < 80_000,
+        "guardian action text should stay below the 10k-token context review cap"
+    );
     assert!(rendered.truncated);
     Ok(())
 }