diff --git a/Packages/macOS/CmuxAgentJournal/Sources/CmuxAgentJournal/AgentNotificationReconciler.swift b/Packages/macOS/CmuxAgentJournal/Sources/CmuxAgentJournal/AgentNotificationReconciler.swift
index ec3116767905..5a21e1e34bbc 100644
--- a/Packages/macOS/CmuxAgentJournal/Sources/CmuxAgentJournal/AgentNotificationReconciler.swift
+++ b/Packages/macOS/CmuxAgentJournal/Sources/CmuxAgentJournal/AgentNotificationReconciler.swift
@@ -99,9 +99,12 @@ public struct AgentNotificationReconciler: Sendable {
             }
             if !session.attentionIdentities.isEmpty {
                 session.phase = .needsInput
-            } else if let declaredPhase = draft.declaredPhase {
-                session.phase = declaredPhase
-                session.rootStopped = declaredPhase == .idle
+            } else if draft.declaredPhase == .idle {
+                // Only an idle declaration (a dismissed idle dialog) settles the
+                // turn. Feed declares every tool result `.running`, which must not
+                // reopen a turn that already completed.
+                session.phase = .idle
+                session.rootStopped = true
             } else if session.rootStopped && session.children.isEmpty {
                 session.phase = .idle
             } else if session.phase == .needsInput {
diff --git a/Packages/macOS/CmuxAgentJournal/Tests/CmuxAgentJournalTests/AgentNotificationReconcilerTests.swift b/Packages/macOS/CmuxAgentJournal/Tests/CmuxAgentJournalTests/AgentNotificationReconcilerTests.swift
index 5bbeb5d8a349..abe2d1e7b869 100644
--- a/Packages/macOS/CmuxAgentJournal/Tests/CmuxAgentJournalTests/AgentNotificationReconcilerTests.swift
+++ b/Packages/macOS/CmuxAgentJournal/Tests/CmuxAgentJournalTests/AgentNotificationReconcilerTests.swift
@@ -315,6 +315,17 @@ struct AgentNotificationReconcilerTests {
         #expect(reconciler.lifecycleEvent(response).draft.declaredPhase == .idle)
     }
 
+    @Test(arguments: ["claude", "codex"])
+    func runningToolResultDoesNotReopenSettledTurn(source: String) {
+        // Feed declares every tool result `.running`; only an idle declaration settles.
+        var reconciler = AgentNotificationReconciler()
+        _ = reconciler.apply(event(1, .turnCompleted, source: source))
+        let result = event(2, .attentionResolved, source: source, request: "ordinary-tool",
+                           notify: false, declaredPhase: .running)
+        #expect(reconciler.apply(result).invalidatedCorrelationKeys.isEmpty)
+        #expect(reconciler.lifecycleEvent(result).draft.declaredPhase == .idle)
+    }
+
     @Test(arguments: ["claude", "codex"])
     func ambiguousOrOlderIdentitylessResponsePreservesAttention(source: String) {
         for responseTurn in [nil, "previous", "turn-1"] as [String?] {