feat: Add more hook types to codewith: onError, onSafetyFlag, and onNewAgentThread (extensible hook framework). — Start a goal

codex-rs/config/src/hook_config.rs

@@ -51,6 +51,12 @@ pub struct HookEventsToml {
     pub subagent_stop: Vec<MatcherGroup>,
     #[serde(rename = "Stop", default)]
     pub stop: Vec<MatcherGroup>,
+    #[serde(rename = "OnError", default)]
+    pub on_error: Vec<MatcherGroup>,
+    #[serde(rename = "OnSafetyFlag", default)]
+    pub on_safety_flag: Vec<MatcherGroup>,
+    #[serde(rename = "OnNewAgentThread", default)]
+    pub on_new_agent_thread: Vec<MatcherGroup>,
 }
 
 impl HookEventsToml {
@@ -66,6 +72,9 @@ impl HookEventsToml {
             subagent_start,
             subagent_stop,
             stop,
+            on_error,
+            on_safety_flag,
+            on_new_agent_thread,
         } = self;
         pre_tool_use.is_empty()
             && permission_request.is_empty()
@@ -77,6 +86,9 @@ impl HookEventsToml {
             && subagent_start.is_empty()
             && subagent_stop.is_empty()
             && stop.is_empty()
+            && on_error.is_empty()
+            && on_safety_flag.is_empty()
+            && on_new_agent_thread.is_empty()
     }
 
     pub fn handler_count(&self) -> usize {
@@ -91,6 +103,9 @@ impl HookEventsToml {
             subagent_start,
             subagent_stop,
             stop,
+            on_error,
+            on_safety_flag,
+            on_new_agent_thread,
         } = self;
         [
             pre_tool_use,
@@ -103,14 +118,17 @@ impl HookEventsToml {
             subagent_start,
             subagent_stop,
             stop,
+            on_error,
+            on_safety_flag,
+            on_new_agent_thread,
         ]
         .into_iter()
         .flatten()
         .map(|group| group.hooks.len())
         .sum()
     }
 
-    pub fn into_matcher_groups(self) -> [(HookEventName, Vec<MatcherGroup>); 10] {
+    pub fn into_matcher_groups(self) -> [(HookEventName, Vec<MatcherGroup>); 13] {
         [
             (HookEventName::PreToolUse, self.pre_tool_use),
             (HookEventName::PermissionRequest, self.permission_request),
@@ -122,6 +140,12 @@ impl HookEventsToml {
             (HookEventName::SubagentStart, self.subagent_start),
             (HookEventName::SubagentStop, self.subagent_stop),
             (HookEventName::Stop, self.stop),
+            (HookEventName::OnError, self.on_error),
+            (HookEventName::OnSafetyFlag, self.on_safety_flag),
+            (
+                HookEventName::OnNewAgentThread,
+                self.on_new_agent_thread,
+            ),
         ]
     }
 }

codex-rs/hooks/src/engine/dispatcher.rs

@@ -61,7 +61,11 @@ pub(crate) fn select_handlers_for_matcher_inputs(
                         .any(|input| matches_matcher(handler.matcher.as_deref(), Some(input)))
                 }
             }
-            HookEventName::UserPromptSubmit | HookEventName::Stop => true,
+            HookEventName::UserPromptSubmit
+            | HookEventName::Stop
+            | HookEventName::OnError
+            | HookEventName::OnSafetyFlag
+            | HookEventName::OnNewAgentThread => true,
         })
         .cloned()
         .collect()
@@ -141,15 +145,19 @@ pub(crate) fn completed_summary(
 
 fn scope_for_event(event_name: HookEventName) -> HookScope {
     match event_name {
-        HookEventName::SessionStart | HookEventName::SubagentStart => HookScope::Thread,
+        HookEventName::SessionStart
+        | HookEventName::SubagentStart
+        | HookEventName::OnNewAgentThread => HookScope::Thread,
         HookEventName::PreToolUse
         | HookEventName::PermissionRequest
         | HookEventName::PostToolUse
         | HookEventName::PreCompact
         | HookEventName::PostCompact
         | HookEventName::UserPromptSubmit
         | HookEventName::SubagentStop
-        | HookEventName::Stop => HookScope::Turn,
+        | HookEventName::Stop
+        | HookEventName::OnError
+        | HookEventName::OnSafetyFlag => HookScope::Turn,
     }
 }
 

codex-rs/hooks/src/engine/mod.rs

@@ -73,6 +73,9 @@ impl ConfiguredHandler {
             codex_protocol::protocol::HookEventName::SubagentStart => "subagent-start",
             codex_protocol::protocol::HookEventName::SubagentStop => "subagent-stop",
             codex_protocol::protocol::HookEventName::Stop => "stop",
+            codex_protocol::protocol::HookEventName::OnError => "on-error",
+            codex_protocol::protocol::HookEventName::OnSafetyFlag => "on-safety-flag",
+            codex_protocol::protocol::HookEventName::OnNewAgentThread => "on-new-agent-thread",
         }
     }
 }

codex-rs/hooks/src/events/common.rs

@@ -115,7 +115,11 @@ pub(crate) fn matcher_pattern_for_event(
         | HookEventName::SubagentStop
         | HookEventName::PreCompact
         | HookEventName::PostCompact => matcher,
-        HookEventName::UserPromptSubmit | HookEventName::Stop => None,
+        HookEventName::UserPromptSubmit
+        | HookEventName::Stop
+        | HookEventName::OnError
+        | HookEventName::OnSafetyFlag
+        | HookEventName::OnNewAgentThread => None,
     }
 }
 

codex-rs/hooks/src/lib.rs

@@ -27,7 +27,7 @@ pub use fleet_comms::fleet_comms_session_start_matcher_group;
 pub use fleet_comms::fleet_comms_session_start_state_key;
 pub use fleet_comms::fleet_comms_session_start_trusted_hash;
 /// Hook event names as they appear in hooks JSON and config files.
-pub const HOOK_EVENT_NAMES: [&str; 10] = [
+pub const HOOK_EVENT_NAMES: [&str; 13] = [
     "PreToolUse",
     "PermissionRequest",
     "PostToolUse",
@@ -38,6 +38,9 @@ pub const HOOK_EVENT_NAMES: [&str; 10] = [
     "SubagentStart",
     "SubagentStop",
     "Stop",
+    "OnError",
+    "OnSafetyFlag",
+    "OnNewAgentThread",
 ];
 
 /// Hook event names whose matcher fields are meaningful during dispatch.
@@ -104,6 +107,9 @@ pub fn hook_event_key_label(event_name: HookEventName) -> &'static str {
         HookEventName::SubagentStart => "subagent_start",
         HookEventName::SubagentStop => "subagent_stop",
         HookEventName::Stop => "stop",
+        HookEventName::OnError => "on_error",
+        HookEventName::OnSafetyFlag => "on_safety_flag",
+        HookEventName::OnNewAgentThread => "on_new_agent_thread",
     }
 }
 

codex-rs/protocol/src/protocol.rs

@@ -1455,6 +1455,9 @@ pub enum HookEventName {
     SubagentStart,
     SubagentStop,
     Stop,
+    OnError,
+    OnSafetyFlag,
+    OnNewAgentThread,
 }
 
 #[derive(Debug, Clone, Copy, Deserialize, Serialize, PartialEq, Eq, JsonSchema, TS)]