apply overrides to picker, add test for ModelInfo/ModelInfoPatch drift

codex-rs/protocol/src/openai_models.rs

@@ -256,7 +256,7 @@ pub struct ModelInfo {
 
 /// User-provided patch for overriding model metadata in local config.
 ///
-/// Every field is optional so users can override only the parts they need.
+/// Every field is optional so users can override only the parts of [`ModelInfo`] they need.
 /// The target model slug is provided by the surrounding map key.
 #[derive(Debug, Serialize, Deserialize, Clone, Default, PartialEq, Eq, TS, JsonSchema)]
 #[serde(default)]
@@ -283,6 +283,7 @@ pub struct ModelInfoPatch {
     pub effective_context_window_percent: Option<i64>,
     pub experimental_supported_tools: Option<Vec<String>>,
     pub input_modalities: Option<Vec<InputModality>>,
+    pub prefer_websockets: Option<bool>,
 }
 
 impl ModelInfo {
@@ -514,6 +515,7 @@ fn nearest_effort(target: ReasoningEffort, supported: &[ReasoningEffort]) -> Rea
 mod tests {
     use super::*;
     use pretty_assertions::assert_eq;
+    use std::collections::BTreeSet;
 
     fn test_model(spec: Option<ModelMessages>) -> ModelInfo {
         ModelInfo {
@@ -697,4 +699,34 @@ mod tests {
         );
         assert_eq!(personality_variables.get_personality_message(None), None);
     }
+
+    #[test]
+    fn model_info_patch_field_coverage_is_explicit() {
+        fn schema_fields<T: JsonSchema>() -> BTreeSet<String> {
+            let schema = schemars::schema_for!(T);
+            let object = schema
+                .schema
+                .object
+                .as_ref()
+                .expect("expected object schema");
+            object.properties.keys().cloned().collect()
+        }
+
+        let model_info_fields = schema_fields::<ModelInfo>();
+        let patch_fields = schema_fields::<ModelInfoPatch>();
+        let intentionally_non_patchable: BTreeSet<String> =
+            ["slug".to_string()].into_iter().collect();
+        let expected_patch_fields: BTreeSet<String> = model_info_fields
+            .difference(&intentionally_non_patchable)
+            .cloned()
+            .collect();
+
+        assert_eq!(patch_fields, expected_patch_fields);
+        for field in &intentionally_non_patchable {
+            assert!(
+                model_info_fields.contains(field),
+                "intentionally_non_patchable contains unknown field: {field}"
+            );
+        }
+    }
 }