Introduce Rollout Policy (#3116)

Have a helper function for deciding if we are rolling out a function or
not

codex-rs/core/src/rollout/mod.rs

@@ -3,6 +3,7 @@
 pub(crate) const SESSIONS_SUBDIR: &str = "sessions";
 
 pub mod list;
+pub(crate) mod policy;
 pub mod recorder;
 
 pub use recorder::RolloutRecorder;

codex-rs/core/src/rollout/policy.rs

@@ -0,0 +1,16 @@
+use codex_protocol::models::ResponseItem;
+
+/// Whether a `ResponseItem` should be persisted in rollout files.
+#[inline]
+pub(crate) fn is_persisted_response_item(item: &ResponseItem) -> bool {
+    match item {
+        ResponseItem::Message { .. }
+        | ResponseItem::Reasoning { .. }
+        | ResponseItem::LocalShellCall { .. }
+        | ResponseItem::FunctionCall { .. }
+        | ResponseItem::FunctionCallOutput { .. }
+        | ResponseItem::CustomToolCall { .. }
+        | ResponseItem::CustomToolCallOutput { .. } => true,
+        ResponseItem::WebSearchCall { .. } | ResponseItem::Other => false,
+    }
+}

codex-rs/core/src/rollout/recorder.rs

@@ -23,6 +23,7 @@ use super::SESSIONS_SUBDIR;
 use super::list::ConversationsPage;
 use super::list::Cursor;
 use super::list::get_conversations;
+use super::policy::is_persisted_response_item;
 use crate::config::Config;
 use crate::conversation_manager::InitialHistory;
 use crate::git_info::GitInfo;
@@ -137,21 +138,11 @@ impl RolloutRecorder {
     pub(crate) async fn record_items(&self, items: &[ResponseItem]) -> std::io::Result<()> {
         let mut filtered = Vec::new();
         for item in items {
-            match item {
+            // Note that function calls may look a bit strange if they are
-                // Note that function calls may look a bit strange if they are
+            // "fully qualified MCP tool calls," so we could consider
-                // "fully qualified MCP tool calls," so we could consider
+            // reformatting them in that case.
-                // reformatting them in that case.
+            if is_persisted_response_item(item) {
-                ResponseItem::Message { .. }
+                filtered.push(item.clone());
-                | ResponseItem::LocalShellCall { .. }
-                | ResponseItem::FunctionCall { .. }
-                | ResponseItem::FunctionCallOutput { .. }
-                | ResponseItem::CustomToolCall { .. }
-                | ResponseItem::CustomToolCallOutput { .. }
-                | ResponseItem::Reasoning { .. } => filtered.push(item.clone()),
-                ResponseItem::WebSearchCall { .. } | ResponseItem::Other => {
-                    // These should never be serialized.
-                    continue;
-                }
             }
         }
         if filtered.is_empty() {
@@ -195,16 +186,11 @@ impl RolloutRecorder {
                 continue;
             }
             match serde_json::from_value::<ResponseItem>(v.clone()) {
-                Ok(item) => match item {
+                Ok(item) => {
-                    ResponseItem::Message { .. }
+                    if is_persisted_response_item(&item) {
-                    | ResponseItem::LocalShellCall { .. }
+                        items.push(item);
-                    | ResponseItem::FunctionCall { .. }
+                    }
-                    | ResponseItem::FunctionCallOutput { .. }
+                }
-                    | ResponseItem::CustomToolCall { .. }
-                    | ResponseItem::CustomToolCallOutput { .. }
-                    | ResponseItem::Reasoning { .. } => items.push(item),
-                    ResponseItem::WebSearchCall { .. } | ResponseItem::Other => {}
-                },
                 Err(e) => {
                     warn!("failed to parse item: {v:?}, error: {e}");
                 }
@@ -305,17 +291,8 @@ async fn rollout_writer(
         match cmd {
             RolloutCmd::AddItems(items) => {
                 for item in items {
-                    match item {
+                    if is_persisted_response_item(&item) {
-                        ResponseItem::Message { .. }
+                        writer.write_line(&item).await?;
-                        | ResponseItem::LocalShellCall { .. }
-                        | ResponseItem::FunctionCall { .. }
-                        | ResponseItem::FunctionCallOutput { .. }
-                        | ResponseItem::CustomToolCall { .. }
-                        | ResponseItem::CustomToolCallOutput { .. }
-                        | ResponseItem::Reasoning { .. } => {
-                            writer.write_line(&item).await?;
-                        }
-                        ResponseItem::WebSearchCall { .. } | ResponseItem::Other => {}
                     }
                 }
             }