diff --git a/apps/web/src/components/ChatView.logic.test.ts b/apps/web/src/components/ChatView.logic.test.ts
index c8afd10d37252055c8efb42f9e5084c512d81cf8..c67ea3f3d5c3bd0259be0ed7b5269f5bf182ae82 100644
--- a/apps/web/src/components/ChatView.logic.test.ts
+++ b/apps/web/src/components/ChatView.logic.test.ts
@@ -41,6 +41,7 @@ import {
   resolveComposerInteractionMode,
   resolveComposerProviderSelection,
   resolveDraftPromotionNavigationTarget,
+  resolveProactiveTurnDiffAction,
   resolveThreadMetadataUpdateForNextTurn,
   resolveSendEnvMode,
   resolveDraftHeroState,
@@ -159,6 +160,80 @@ describe("proactive panels", () => {
       }),
     ).toBe(false);
   });
+
+  it("opens a completed turn diff only for changed files", () => {
+    const changedCheckpoint = {
+      status: "ready",
+      files: [{ path: "src/app.ts", kind: "modified", additions: 1, deletions: 0 }],
+    } satisfies Pick<TurnDiffSummary, "status" | "files">;
+    const unchangedCheckpoint = {
+      status: "ready",
+      files: [],
+    } satisfies Pick<TurnDiffSummary, "status" | "files">;
+
+    expect(
+      resolveProactiveTurnDiffAction({
+        checkpoint: changedCheckpoint,
+        isGitRepo: true,
+        activeSurfaceKind: null,
+      }),
+    ).toBe("open");
+    expect(
+      resolveProactiveTurnDiffAction({
+        checkpoint: unchangedCheckpoint,
+        isGitRepo: true,
+        activeSurfaceKind: null,
+      }),
+    ).toBe("ignore");
+  });
+
+  it("waits for definitive checkpoint and repository state", () => {
+    const missingCheckpoint = {
+      status: "missing",
+      files: [],
+    } satisfies Pick<TurnDiffSummary, "status" | "files">;
+    const changedCheckpoint = {
+      status: "ready",
+      files: [{ path: "src/app.ts", kind: "modified", additions: 1, deletions: 0 }],
+    } satisfies Pick<TurnDiffSummary, "status" | "files">;
+
+    expect(
+      resolveProactiveTurnDiffAction({
+        checkpoint: undefined,
+        isGitRepo: true,
+        activeSurfaceKind: null,
+      }),
+    ).toBe("defer");
+    expect(
+      resolveProactiveTurnDiffAction({
+        checkpoint: missingCheckpoint,
+        isGitRepo: true,
+        activeSurfaceKind: null,
+      }),
+    ).toBe("defer");
+    expect(
+      resolveProactiveTurnDiffAction({
+        checkpoint: changedCheckpoint,
+        isGitRepo: undefined,
+        activeSurfaceKind: null,
+      }),
+    ).toBe("defer");
+  });
+
+  it("keeps an active pull request above a completed turn diff", () => {
+    const changedCheckpoint = {
+      status: "ready",
+      files: [{ path: "src/app.ts", kind: "modified", additions: 1, deletions: 0 }],
+    } satisfies Pick<TurnDiffSummary, "status" | "files">;
+
+    expect(
+      resolveProactiveTurnDiffAction({
+        checkpoint: changedCheckpoint,
+        isGitRepo: true,
+        activeSurfaceKind: "pull-request",
+      }),
+    ).toBe("ignore");
+  });
 });
 
 describe("toolGroupConsumesUpwardNavigation", () => {
diff --git a/apps/web/src/components/ChatView.logic.ts b/apps/web/src/components/ChatView.logic.ts
index 4a0b9f5761037fc56d385240ce472424f48d1586..10c2fd4710ee145cb65f3a7183fc258ff9d0bad7 100644
--- a/apps/web/src/components/ChatView.logic.ts
+++ b/apps/web/src/components/ChatView.logic.ts
@@ -121,6 +121,24 @@ export function shouldOpenProactiveTurnDiff(input: {
   );
 }
 
+export function resolveProactiveTurnDiffAction(input: {
+  checkpoint: Pick<TurnDiffSummary, "status" | "files"> | undefined;
+  isGitRepo: boolean | undefined;
+  activeSurfaceKind: RightPanelSurface["kind"] | null;
+}): "defer" | "ignore" | "open" {
+  if (input.activeSurfaceKind === "pull-request") return "ignore";
+  if (input.checkpoint === undefined || input.checkpoint.status === "missing") return "defer";
+  if (input.isGitRepo === undefined) return "defer";
+  if (
+    !input.isGitRepo ||
+    input.checkpoint.status !== "ready" ||
+    input.checkpoint.files.length === 0
+  ) {
+    return "ignore";
+  }
+  return "open";
+}
+
 export function codexArtifactTemplatePromptToAppend(
   currentDraft: string,
   template: CodexArtifactTemplate,
diff --git a/apps/web/src/components/ChatView.tsx b/apps/web/src/components/ChatView.tsx
index ccd970e6dda3897175aacb5f16eaf6947720fcc9..cfbeb3aa7f72f4eead29eaf20b29be25e68ce588 100644
--- a/apps/web/src/components/ChatView.tsx
+++ b/apps/web/src/components/ChatView.tsx
@@ -385,6 +385,7 @@ import {
   resolveComposerInteractionMode,
   resolveComposerProviderSelection,
   resolveDraftHeroState,
+  resolveProactiveTurnDiffAction,
   resolveThreadMetadataUpdateForNextTurn,
   resolveSendEnvMode,
   revokeBlobPreviewUrl,
@@ -3922,18 +3923,21 @@ export default function ChatView(props: ChatViewProps) {
       : null;
     const eligibleCompletion =
       settings.proactivePanelsEnabled && !shouldUseRightPanelSheet && newlyCompletedTurnId !== null;
-    const checkpointReady =
-      eligibleCompletion &&
-      activeThread?.checkpoints.some((checkpoint) => checkpoint.turnId === newlyCompletedTurnId) ===
-        true;
-    const shouldOpenTurn = checkpointReady && gitStatusQuery.data?.isRepo === true;
-    const shouldDeferCompletion =
-      eligibleCompletion && !shouldOpenTurn && gitStatusQuery.data?.isRepo !== false;
+    const completedCheckpoint = eligibleCompletion
+      ? activeThread?.checkpoints.find((checkpoint) => checkpoint.turnId === newlyCompletedTurnId)
+      : undefined;
+    const diffAction = eligibleCompletion
+      ? resolveProactiveTurnDiffAction({
+          checkpoint: completedCheckpoint,
+          isGitRepo: gitStatusQuery.data?.isRepo,
+          activeSurfaceKind: activeRightPanelSurface?.kind ?? null,
+        })
+      : "ignore";
     proactiveTurnObservationRef.current = {
       threadKey: activeThreadKey,
-      runningTurnId: shouldDeferCompletion ? (previousRunningTurnId ?? null) : activeRunningTurnId,
+      runningTurnId: diffAction === "defer" ? (previousRunningTurnId ?? null) : activeRunningTurnId,
     };
-    if (!shouldOpenTurn || newlyCompletedTurnId === null) return;
+    if (diffAction !== "open" || newlyCompletedTurnId === null) return;
 
     useDiffPanelStore.getState().selectTurn(activeThreadRef, newlyCompletedTurnId);
     useRightPanelStore.getState().open(activeThreadRef, "diff");
@@ -3945,6 +3949,7 @@ export default function ChatView(props: ChatViewProps) {
     activeRunningTurnId,
     activeThreadKey,
     activeThreadRef,
+    activeRightPanelSurface?.kind,
     clientSettingsHydrated,
     gitStatusQuery.data?.isRepo,
     isServerThread,
diff --git a/apps/web/src/components/settings/SettingsPanels.tsx b/apps/web/src/components/settings/SettingsPanels.tsx
index d78828da5cfe89c2ffd32bdf22ad7be2b999691b..b0344b6403930f435d75affb79d19652083ee80a 100644
--- a/apps/web/src/components/settings/SettingsPanels.tsx
+++ b/apps/web/src/components/settings/SettingsPanels.tsx
@@ -2308,7 +2308,7 @@ export function GeneralSettingsPanel() {
 
         <SettingsRow
           {...searchableSetting("proactive-panels")}
-          description="Open linked pull requests when found and turn diffs when work finishes."
+          description="Open linked pull requests when found and turn diffs when work changes files."
           resetAction={
             settings.proactivePanelsEnabled !== DEFAULT_UNIFIED_SETTINGS.proactivePanelsEnabled ? (
               <SettingResetButton
diff --git a/docs/user/source-control.md b/docs/user/source-control.md
index 482b3ccd1f1246e290babc1b1dd76205005e2dce..71f6548dd6b9339bf3ec93b3eef07bd54645b99d 100644
--- a/docs/user/source-control.md
+++ b/docs/user/source-control.md
@@ -64,7 +64,7 @@ T3 Code works with the platforms your team already uses:
   changed files as folders and jump straight to any of them. The toolbar toggle remembers your
   choice.
 - Enable **Settings → General → Proactive panels** to open a newly linked review automatically and
-  switch to the completed turn's diff when agent work finishes
+  switch to the completed turn's diff when agent work changes files. An open review stays in front
 - Open the review directly in your browser with one click
 - If T3 Code cannot load a GitHub pull request, including when GitHub rate limits requests, use
   **Open on GitHub** in the error view