5 files changed, 98 insertions, 13 deletions
diff --git a/src/integration/assets/opencode/herdr-agent-state.js b/src/integration/assets/opencode/herdr-agent-state.js
index 2840c221..45032335 100644
--- a/src/integration/assets/opencode/herdr-agent-state.js
+++ b/src/integration/assets/opencode/herdr-agent-state.js
@@ -2,7 +2,7 @@
 // managed by herdr; reinstalling or updating the integration overwrites this file.
 // add custom hooks/plugins beside this file instead of editing it.
 // HERDR_INTEGRATION_ID=opencode
-// HERDR_INTEGRATION_VERSION=10
+// HERDR_INTEGRATION_VERSION=11
 
 import net from "node:net";
 
@@ -13,8 +13,8 @@ let requestChain = Promise.resolve();
 let reportedRootSessionID;
 
 // Track child sessions so their events cannot replace the pane's root session.
-// Their user prompts still project state without attaching the child session id.
-const childSessions = new Set();
+// User prompts carry the root id to preserve its identity and cross-talk guard.
+const childSessions = new Map();
 const CHILD_EVENT_STATES = new Map([
   ["permission.asked", "blocked"],
   ["question.asked", "blocked"],
@@ -141,12 +141,16 @@ export const HerdrAgentStatePlugin = async () => {
 
       const info = properties.info;
       if (info?.id && info.parentID) {
-        childSessions.add(info.id);
+        childSessions.set(info.id, info.parentID);
       }
       if (sessionID && childSessions.has(sessionID)) {
         const state = CHILD_EVENT_STATES.get(type);
         if (state) {
-          await reportState(state);
+          let rootSessionID = sessionID;
+          while (childSessions.has(rootSessionID)) {
+            rootSessionID = childSessions.get(rootSessionID);
+          }
+          await reportState(state, rootSessionID);
         }
         return;
       }
diff --git a/src/integration/assets/opencode/herdr-agent-state.test.ts b/src/integration/assets/opencode/herdr-agent-state.test.ts
index 6f8ee590..a3eea848 100644
--- a/src/integration/assets/opencode/herdr-agent-state.test.ts
+++ b/src/integration/assets/opencode/herdr-agent-state.test.ts
@@ -167,7 +167,6 @@ test("reports child prompts without replacing the root session", async () => {
     event: {
       type: "session.created",
       properties: {
-        sessionID: "child-session",
         info: { id: "child-session", parentID: "root-session" },
       },
     },
@@ -188,11 +187,39 @@ test("reports child prompts without replacing the root session", async () => {
     "working",
   ]);
   expect(requests.map(requestSessionID)).toEqual([
-    undefined,
-    undefined,
-    undefined,
-    undefined,
-    undefined,
+    "root-session",
+    "root-session",
+    "root-session",
+    "root-session",
+    "root-session",
+  ]);
+});
+
+test("routes nested child prompts to their own root, not the last active root", async () => {
+  const plugin = await loadPlugin();
+  for (const info of [
+    { id: "child-session", parentID: "root-session" },
+    { id: "nested-session", parentID: "child-session" },
+  ]) {
+    await plugin.event({ event: { type: "session.created", properties: { info } } });
+  }
+  await plugin["chat.message"]({ sessionID: "other-root" });
+  await plugin.event({
+    event: { type: "permission.asked", properties: { sessionID: "nested-session" } },
+  });
+  await plugin.event({
+    event: { type: "permission.replied", properties: { sessionID: "nested-session" } },
+  });
+  await plugin.event({
+    event: { type: "session.idle", properties: { sessionID: "nested-session" } },
+  });
+  await plugin["chat.message"]({ sessionID: "nested-session" });
+
+  expect(requests.map(requestState)).toEqual(["working", "blocked", "working"]);
+  expect(requests.map(requestSessionID)).toEqual([
+    "other-root",
+    "root-session",
+    "root-session",
   ]);
 });
 
diff --git a/src/integration/assets/opencode/herdr-tui-session.js b/src/integration/assets/opencode/herdr-tui-session.js
index b5be5bbc..f4f08d57 100644
--- a/src/integration/assets/opencode/herdr-tui-session.js
+++ b/src/integration/assets/opencode/herdr-tui-session.js
@@ -1,7 +1,7 @@
 // installed by herdr
 // managed by herdr; reinstalling or updating the integration overwrites this file.
 // HERDR_INTEGRATION_ID=opencode-tui
-// HERDR_INTEGRATION_VERSION=10
+// HERDR_INTEGRATION_VERSION=11
 
 import net from "node:net";
 
diff --git a/src/integration/mod.rs b/src/integration/mod.rs
index fd0839f4..3f7176b3 100644
--- a/src/integration/mod.rs
+++ b/src/integration/mod.rs
@@ -170,7 +170,7 @@ const OPENCODE_PLUGIN_ASSET: &str = include_str!("assets/opencode/herdr-agent-st
 const OPENCODE_TUI_PLUGIN_INSTALL_NAME: &str = "herdr-tui-session.js";
 const OPENCODE_TUI_PLUGIN_SPEC: &str = "./herdr-tui-session.js";
 const OPENCODE_TUI_PLUGIN_ASSET: &str = include_str!("assets/opencode/herdr-tui-session.js");
-const OPENCODE_INTEGRATION_VERSION: u32 = 10;
+const OPENCODE_INTEGRATION_VERSION: u32 = 11;
 const KILO_PLUGIN_INSTALL_NAME: &str = "herdr-agent-state.js";
 const KILO_PLUGIN_ASSET: &str = include_str!("assets/kilo/herdr-agent-state.js");
 const KILO_INTEGRATION_VERSION: u32 = 4;
diff --git a/src/terminal/state.rs b/src/terminal/state.rs
index ee170198..dc28af10 100644
--- a/src/terminal/state.rs
+++ b/src/terminal/state.rs
@@ -4786,6 +4786,60 @@ mod tests {
     }
 
     #[test]
+    fn opencode_child_prompt_reports_with_root_id_preserve_lifecycle_authority() {
+        let mut terminal = test_terminal();
+        let root = crate::agent_resume::AgentSessionRef::id("opencode-root").unwrap();
+        anchor_full_lifecycle_session(
+            &mut terminal,
+            Agent::OpenCode,
+            "herdr:opencode",
+            "opencode",
+            root.clone(),
+        );
+
+        // The plugin projects child permission/question events onto their root.
+        for (seq, state) in [
+            (20, AgentState::Working),
+            (21, AgentState::Blocked),
+            (22, AgentState::Working),
+            (23, AgentState::Idle),
+        ] {
+            let mutation = terminal
+                .set_hook_authority_with_session_ref(
+                    "herdr:opencode".into(),
+                    "opencode".into(),
+                    state,
+                    None,
+                    Some(root.clone()),
+                    Some(seq),
+                )
+                .expect("root-scoped lifecycle report should be accepted");
+            assert!(!mutation.session_ref_changed);
+            assert_eq!(terminal.state, state);
+            assert_eq!(
+                terminal
+                    .hook_authority
+                    .as_ref()
+                    .unwrap()
+                    .session_ref
+                    .as_ref(),
+                Some(&root)
+            );
+        }
+
+        let foreign_child_prompt = terminal.set_hook_authority_with_session_ref(
+            "herdr:opencode".into(),
+            "opencode".into(),
+            AgentState::Blocked,
+            None,
+            crate::agent_resume::AgentSessionRef::id("opencode-other-root"),
+            Some(24),
+        );
+        assert!(foreign_child_prompt.is_none());
+        assert_eq!(terminal.state, AgentState::Idle);
+    }
+
+    #[test]
     fn opencode_tui_selection_reanchors_full_lifecycle_authority() {
         let mut terminal = test_terminal();
         let old_session = crate::agent_resume::AgentSessionRef::id("opencode-newer").unwrap();