diff --git a/apps/desktop/src/app/session/hooks/use-session-actions/index.ts b/apps/desktop/src/app/session/hooks/use-session-actions/index.ts
index 266a33b65fd..9bcabd6d3bb 100644
--- a/apps/desktop/src/app/session/hooks/use-session-actions/index.ts
+++ b/apps/desktop/src/app/session/hooks/use-session-actions/index.ts
@@ -504,7 +504,9 @@ export function useSessionActions({
           upsertOptimisticSession(created, stored, null, null)
         }
 
-        const runtimeInfo = applyRuntimeInfo(created.info)
+        // A tile lives in its OWN worktree — it must not publish its cwd/branch
+        // into the composer atoms the main pane renders from.
+        const runtimeInfo = applyRuntimeInfo(created.info, { foreground: false })
         updateSessionState(created.session_id, state => (runtimeInfo ? { ...state, ...runtimeInfo } : state), stored)
 
         openSessionTile(stored, dir)
@@ -1182,7 +1184,9 @@ export function useSessionActions({
           routedSessionId
         )
 
-        const runtimeInfo = applyRuntimeInfo(branched.info)
+        // The branch opens as its own tile in the parent's worktree, not as the
+        // primary session — keep its runtime out of the main composer atoms.
+        const runtimeInfo = applyRuntimeInfo(branched.info, { foreground: false })
         patchSessionWorkspace(routedSessionId, runtimeInfo?.cwd)
 
         if (runtimeInfo) {