diff --git a/packages/server/src/server/agent/providers/codex-app-server-agent.test.ts b/packages/server/src/server/agent/providers/codex-app-server-agent.test.ts
index 9986357cf4..a73ff0c490 100644
--- a/packages/server/src/server/agent/providers/codex-app-server-agent.test.ts
+++ b/packages/server/src/server/agent/providers/codex-app-server-agent.test.ts
@@ -227,6 +227,67 @@ function deferred<T>() {
   return { promise, resolve };
 }
 
+describe("Codex file-change approvals", () => {
+  test("file-change approval includes the matching started patch", async () => {
+    const appServer = createFakeCodexAppServer();
+    const { session } = await startPublicSteeringSession(appServer);
+    try {
+      for (const [id, filePath, diff] of [
+        ["file-alpha", "/workspace/project/alpha.txt", "@@ -1 +1 @@\n-blue\n+green\n"],
+        ["file-beta", "/workspace/project/beta.txt", "@@ -1 +1 @@\n-small\n+large\n"],
+      ]) {
+        const started = waitForTimelineToolCall(session, id);
+        appServer.child.stdout.write(
+          `${JSON.stringify({
+            method: "item/started",
+            params: {
+              threadId: "thread-1",
+              turnId: "native-A",
+              item: {
+                type: "fileChange",
+                id,
+                status: "inProgress",
+                changes: [{ path: filePath, kind: { type: "update", move_path: null }, diff }],
+              },
+            },
+          })}\n`,
+        );
+        await started;
+      }
+      const permission = waitForNextPermission(session);
+      appServer.requestFileChangeApproval({
+        itemId: "file-alpha",
+        threadId: "thread-1",
+        turnId: "native-A",
+        reason: "Apply the patch",
+      });
+
+      expect((await permission).request).toEqual({
+        id: "permission-file-alpha",
+        provider: "codex",
+        name: "CodexFileChange",
+        kind: "tool",
+        title: "Apply file changes",
+        description: "Apply the patch",
+        detail: {
+          type: "edit",
+          filePath: "alpha.txt",
+          unifiedDiff: "@@ -1 +1 @@\n-blue\n+green\n",
+        },
+        metadata: { itemId: "file-alpha", threadId: "thread-1", turnId: "native-A" },
+      });
+
+      await session.respondToPermission("permission-file-alpha", { behavior: "allow" });
+      await expect(appServer.waitForApprovalDecision("file-alpha")).resolves.toEqual({
+        decision: "accept",
+      });
+      appServer.assertNoErrors();
+    } finally {
+      await session.close();
+    }
+  });
+});
+
 describe("Codex active-turn steering admission", () => {
   test("steers an accepted turn whose native id arrives after startTurn returns", async () => {
     const appServer = createFakeCodexAppServer({
diff --git a/packages/server/src/server/agent/providers/codex-app-server-agent.ts b/packages/server/src/server/agent/providers/codex-app-server-agent.ts
index cc667b2494..86f7eb073b 100644
--- a/packages/server/src/server/agent/providers/codex-app-server-agent.ts
+++ b/packages/server/src/server/agent/providers/codex-app-server-agent.ts
@@ -3483,6 +3483,7 @@ export class CodexAppServerAgentSession implements AgentSession {
   private pendingReasoning = new Map<string, string[]>();
   private pendingCommandOutputDeltas = new Map<string, string[]>();
   private pendingFileChangeOutputDeltas = new Map<string, string[]>();
+  private pendingToolCallDetails = new Map<string, ToolCallTimelineItem["detail"]>();
   private pendingAssistantMessageBoundary = false;
   private terminalCommandByProcessId = new Map<string, string>();
   // The root thread's still-running command process ids, keyed by the native turn that
@@ -5251,6 +5252,7 @@ export class CodexAppServerAgentSession implements AgentSession {
   async close(): Promise<void> {
     this.closed = true;
     this.clearPendingPermissions();
+    this.pendingToolCallDetails.clear();
     this.pendingSubAgentNotificationsByThreadId.clear();
     this.subscribers.clear();
     this.startupEvents = null;
@@ -6416,6 +6418,7 @@ export class CodexAppServerAgentSession implements AgentSession {
     this.pendingReasoning.clear();
     this.pendingCommandOutputDeltas.clear();
     this.pendingFileChangeOutputDeltas.clear();
+    this.pendingToolCallDetails.clear();
     this.pendingAssistantMessageBoundary = false;
     this.warnedIncompleteEditToolCallIds.clear();
     this.pendingRootCompactionItemIds.clear();
@@ -6789,6 +6792,9 @@ export class CodexAppServerAgentSession implements AgentSession {
     if (shouldIgnoreMirroredLifecycleItem(parsed.source, parsed.item)) {
       return;
     }
+    if (parsed.item.id) {
+      this.pendingToolCallDetails.delete(parsed.item.id);
+    }
     this.receiveAsyncQuestion(parsed.threadId, parsed.item);
     if (this.isUserMessageItem(parsed.item)) {
       await this.handleUserMessageItem(parsed);
@@ -6984,6 +6990,7 @@ export class CodexAppServerAgentSession implements AgentSession {
     if (!timelineItem || timelineItem.type !== "tool_call") {
       return;
     }
+    this.pendingToolCallDetails.set(timelineItem.callId, timelineItem.detail);
     const registeredChildThreadIds = this.registerSubAgentToolCall({
       timelineItem,
       rawItem: parsed.item,
@@ -7270,7 +7277,7 @@ export class CodexAppServerAgentSession implements AgentSession {
       kind: "tool",
       title: "Apply file changes",
       description: parsed.reason ?? undefined,
-      detail: {
+      detail: this.pendingToolCallDetails.get(parsed.itemId) ?? {
         type: "unknown",
         input: {
           reason: parsed.reason ?? null,