Add Guardian V3 feature configuration (#56459)

## What changed

Register `guardianv3` as an under-development feature disabled by default. Accept either a boolean toggle or a table with an optional `enabled` field, and include both forms in the configuration schema.

## Testing

Add coverage for boolean and table configuration, default behavior, and profile overrides, including inheritance when a profile omits `enabled`.

GitOrigin-RevId: 75333be61b2e336e22fef907d6363b70f9f7225b

codex-rs/config/src/schema.rs

@@ -90,6 +90,15 @@ pub fn features_schema(schema_gen: &mut SchemaGenerator) -> Schema {
             );
             continue;
         }
+        if feature.id == codex_features::Feature::GuardianV3 {
+            validation.properties.insert(
+                feature.key.to_string(),
+                schema_gen.subschema_for::<codex_features::FeatureToml<
+                    codex_features::GuardianV3ConfigToml,
+                >>(),
+            );
+            continue;
+        }
         if feature.id == codex_features::Feature::MultiAgentV2 {
             validation.properties.insert(
                 feature.key.to_string(),

codex-rs/core/config.schema.json

@@ -988,6 +988,9 @@
             "guardianv2_decisions_comparison": {
               "type": "boolean"
             },
+            "guardianv3": {
+              "$ref": "#/definitions/FeatureToml_for_GuardianV3ConfigToml"
+            },
             "hooks": {
               "type": "boolean"
             },
@@ -1694,6 +1697,16 @@
         }
       ]
     },
+    "FeatureToml_for_GuardianV3ConfigToml": {
+      "anyOf": [
+        {
+          "type": "boolean"
+        },
+        {
+          "$ref": "#/definitions/GuardianV3ConfigToml"
+        }
+      ]
+    },
     "FeatureToml_for_MultiAgentV2ConfigToml": {
       "anyOf": [
         {
@@ -2145,6 +2158,16 @@
       ],
       "type": "string"
     },
+    "GuardianV3ConfigToml": {
+      "additionalProperties": false,
+      "description": "User-configurable settings for Guardian V3.",
+      "properties": {
+        "enabled": {
+          "type": "boolean"
+        }
+      },
+      "type": "object"
+    },
     "History": {
       "additionalProperties": false,
       "description": "Settings that govern if and what will be written to `~/.codex/history.jsonl`.",
@@ -7506,6 +7529,9 @@
         "guardianv2_decisions_comparison": {
           "type": "boolean"
         },
+        "guardianv3": {
+          "$ref": "#/definitions/FeatureToml_for_GuardianV3ConfigToml"
+        },
         "hooks": {
           "type": "boolean"
         },

codex-rs/features/src/feature_configs.rs

@@ -284,6 +284,20 @@ where
     Ok(feature)
 }
 
+/// User-configurable settings for Guardian V3.
+#[derive(Serialize, Deserialize, Debug, Clone, Default, PartialEq, Eq, JsonSchema)]
+#[serde(deny_unknown_fields)]
+pub struct GuardianV3ConfigToml {
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub enabled: Option<bool>,
+}
+
+impl FeatureConfig for GuardianV3ConfigToml {
+    fn enabled(&self) -> Option<bool> {
+        self.enabled
+    }
+}
+
 #[derive(Serialize, Deserialize, Debug, Clone, Default, PartialEq, Eq, JsonSchema)]
 #[serde(deny_unknown_fields)]
 pub struct MultiAgentV2ConfigToml {

codex-rs/features/src/lib.rs

@@ -28,6 +28,7 @@ pub use feature_configs::GuardianV2ConfigToml;
 pub use feature_configs::GuardianV2ReviewScopeConfigToml;
 pub use feature_configs::GuardianV2TranscriptConfigToml;
 pub use feature_configs::GuardianV2TranscriptSource;
+pub use feature_configs::GuardianV3ConfigToml;
 pub use feature_configs::MultiAgentV2ConfigToml;
 pub use feature_configs::NetworkProxyConfigToml;
 pub use feature_configs::NetworkProxyDomainPermissionToml;
@@ -401,6 +402,8 @@ pub enum Feature {
     GuardianV2,
     /// Run Decisions alongside Guardian V2 for measurement without changing approvals.
     GuardianV2DecisionsComparison,
+    /// Enable Guardian V3 integrations.
+    GuardianV3,
     /// Removed compatibility flag for the unused Guardian extension prototype.
     GuardianExt,
     /// Enable persisted thread goals and automatic goal continuation.
@@ -900,6 +903,8 @@ pub struct FeaturesToml {
     )]
     pub guardianv2: Option<FeatureToml<GuardianV2ConfigToml>>,
     #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub guardianv3: Option<FeatureToml<GuardianV3ConfigToml>>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
     pub multi_agent_v2: Option<FeatureToml<MultiAgentV2ConfigToml>>,
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub token_budget: Option<FeatureToml<TokenBudgetConfigToml>>,
@@ -962,6 +967,9 @@ impl FeaturesToml {
         {
             entries.insert(Feature::GuardianThreadContext.key().to_string(), enabled);
         }
+        if let Some(enabled) = self.guardianv3.as_ref().and_then(FeatureToml::enabled) {
+            entries.insert(Feature::GuardianV3.key().to_string(), enabled);
+        }
         if let Some(enabled) = self.multi_agent_v2.as_ref().and_then(FeatureToml::enabled) {
             entries.insert(Feature::MultiAgentV2.key().to_string(), enabled);
         }
@@ -1964,6 +1972,12 @@ pub const FEATURES: &[FeatureSpec] = &[
         stage: Stage::UnderDevelopment,
         default_enabled: false,
     },
+    FeatureSpec {
+        id: Feature::GuardianV3,
+        key: "guardianv3",
+        stage: Stage::UnderDevelopment,
+        default_enabled: false,
+    },
     FeatureSpec {
         id: Feature::GuardianExt,
         key: "guardian_ext",

codex-rs/features/src/tests.rs

@@ -211,6 +211,43 @@ fn guardian_v2_feature_config_preserves_boolean_toggle() {
     );
 }
 
+#[test]
+fn guardian_v3_feature_config_resolves_base_and_profile_toggles() {
+    for (base, profile, enabled) in [
+        ("guardianv3 = true", "", true),
+        ("guardianv3 = false", "", false),
+        ("[guardianv3]", "", false),
+        ("[guardianv3]\nenabled = true", "", true),
+        ("[guardianv3]\nenabled = false", "", false),
+        (
+            "[guardianv3]\nenabled = true",
+            "[guardianv3]\nenabled = false",
+            false,
+        ),
+        (
+            "[guardianv3]\nenabled = false",
+            "[guardianv3]\nenabled = true",
+            true,
+        ),
+        ("[guardianv3]\nenabled = true", "[guardianv3]", true),
+    ] {
+        let base = toml::from_str::<FeaturesToml>(base).expect("base features");
+        let profile = toml::from_str::<FeaturesToml>(profile).expect("profile features");
+        let features = Features::from_sources(
+            FeatureConfigSource {
+                features: Some(&base),
+                ..Default::default()
+            },
+            FeatureConfigSource {
+                features: Some(&profile),
+                ..Default::default()
+            },
+            FeatureOverrides::default(),
+        );
+        assert_eq!(features.enabled(Feature::GuardianV3), enabled);
+    }
+}
+
 #[test]
 fn guardian_thread_context_is_ignored_with_a_migration_notice() {
     let enabled_context = "[guardianv2]\nthread_context = true";