fix(herdr): use targeted splits for mirrored reviews

README.md

@@ -77,6 +77,11 @@ placement = "overlay"   # overlay (full tab, default) | split | popup
 `plannotator-tui config` prints the file's path and the values in effect. The `herdr/`
 directory in this repo is the development manifest; users should install Herdr Annotate.
 
+Actions forwarded by Herdr Mirror default to a split beside the invoking remote
+pane. Mirror does not preserve overlay presentation, and Herdr 0.8.2 opens an
+overlay in its server's active tab, which can differ from the tab you are viewing.
+An explicit `--placement` or `PLANNOTATOR_TUI_PLACEMENT` still takes precedence.
+
 ## Agent replies
 
 `plannotator-tui last` finds the transcript of the agent that launched your shell and shows a

crates/plannotator-tui/src/herdr/context.rs

@@ -84,7 +84,7 @@ impl HerdrEnv {
     /// The focused pane from the context, only when Herdr saw an agent in it.
     pub(crate) fn focused_agent_pane(&self) -> Option<Target> {
         let context = self.context.as_ref()?;
-        let agent = context.focused_pane_agent.clone()?;
+        let agent = context.focused_pane_agent.clone().filter(|agent| !agent.trim().is_empty())?;
         Some(Target { pane: context.focused_pane_id.clone()?, agent: Some(agent) })
     }
 
@@ -171,6 +171,9 @@ mod tests {
         let shell =
             env(&[("HERDR_ENV", "1"), ("HERDR_PLUGIN_CONTEXT_JSON", r#"{"focused_pane_id":"w1:p2"}"#)]);
         assert_eq!(shell.delivery_target(), None);
+        let mirror_shell =
+            env(&[("HERDR_PLUGIN_CONTEXT_JSON", r#"{"focused_pane_id":"w1:p2","focused_pane_agent":""}"#)]);
+        assert_eq!(mirror_shell.delivery_target(), None);
     }
 
     #[test]

crates/plannotator-tui/src/herdr/launch.rs

@@ -194,6 +194,15 @@ pub(crate) fn plan(env: &HerdrEnv, config: &Config, args: OpenArgs, cwd: &Path)
     let placement = match (args.placement, env.placement.as_deref()) {
         (Some(p), _) => p,
         (None, Some(text)) => text.parse().context("PLANNOTATOR_TUI_PLACEMENT")?,
+        // Mirror imports ordinary panes, not the remote client's overlays. Herdr
+        // 0.8.2 also places overlays in its globally active tab, which may differ
+        // from the invoking mirror. A targeted split reaches the intended tab.
+        (None, None)
+            if config.herdr.placement == Placement::Overlay
+                && context.and_then(|c| c.invocation_source.as_deref()) == Some("mirror") =>
+        {
+            Placement::Split
+        }
         (None, None) => config.herdr.placement,
     };
 

crates/plannotator-tui/src/herdr/launch/tests.rs

@@ -77,6 +77,40 @@ fn agent_skill_delivers_to_and_splits_beside_the_calling_pane() {
     std::fs::remove_dir_all(&root).expect("cleanup");
 }
 
+#[test]
+fn mirror_defaults_to_a_split_next_to_the_remote_invoking_pane() {
+    let context = HerdrContext {
+        focused_pane_id: Some("w2:p4".into()),
+        focused_pane_agent: Some("codex".into()),
+        invocation_source: Some("mirror".into()),
+        ..HerdrContext::default()
+    };
+    let env = env(None, Some(context));
+    let launch = plan(&env, &Config::default(), OpenArgs::default(), Path::new("/"))
+        .expect("plans a mirrored document");
+    assert_eq!(launch.placement, Placement::Split);
+    assert!(argv(&launch).windows(2).any(|pair| pair == ["--target-pane", "w2:p4"]));
+    let agent = r#"{"result":{"agent":{"agent":"codex","agent_session":{"kind":"path","value":"/sessions/exact.jsonl"}}}}"#;
+    let last = plan_last(&env, &Config::default(), OpenArgs::default(), Path::new("/"), None, Some(agent))
+        .expect("plans the same pane's reply");
+    assert_eq!(last.placement, Placement::Split);
+    assert_eq!(last.target_pane.as_deref(), Some("w2:p4"));
+    assert_eq!(last.session, Some(AgentSession::Path("/sessions/exact.jsonl".into())));
+}
+
+#[test]
+fn explicit_placement_still_wins_over_the_mirror_default() {
+    let mut env =
+        env(None, Some(HerdrContext { invocation_source: Some("mirror".into()), ..HerdrContext::default() }));
+    env.placement = Some("popup".into());
+    let launch =
+        plan(&env, &Config::default(), OpenArgs::default(), Path::new("/")).expect("environment placement");
+    assert_eq!(launch.placement, Placement::Popup);
+    let args = OpenArgs { placement: Some(Placement::Overlay), ..OpenArgs::default() };
+    let launch = plan(&env, &Config::default(), args, Path::new("/")).expect("explicit argument placement");
+    assert_eq!(launch.placement, Placement::Overlay);
+}
+
 #[test]
 fn ctrl_click_opens_the_linked_file() {
     let root = temp_folder("click");