diff --git a/server/src/__tests__/issue-closed-workspace-routes.test.ts b/server/src/__tests__/issue-closed-workspace-routes.test.ts
index b15070a906..c657ebb006 100644
--- a/server/src/__tests__/issue-closed-workspace-routes.test.ts
+++ b/server/src/__tests__/issue-closed-workspace-routes.test.ts
@@ -308,6 +308,56 @@ describe.sequential("closed isolated workspace issue routes", () => {
     expect(mockIssueService.addComment).not.toHaveBeenCalled();
   });
 
+  it("accepts a plain comment on a done issue without touching the closed workspace", async () => {
+    // A comment that does not resume a terminal issue is a pure record: it
+    // must not rebuild the worktree, and it must not be blocked by a
+    // workspace it never needed.
+    mockIssueService.getById.mockResolvedValue({ ...makeIssue(), status: "done", assigneeAgentId: null });
+    mockIssueService.addComment.mockResolvedValue({ id: "comment-1", body: "decision recorded" });
+
+    const res = await request(createApp())
+      .post(`/api/issues/${issueId}/comments`)
+      .send({ body: "decision recorded" });
+
+    expect(res.status).toBe(201);
+    expect(mockIssueService.addComment).toHaveBeenCalledTimes(1);
+    expect(mockExecutionWorkspaceService.reopenClosedIsolatedExecutionWorkspaceForIssue).not.toHaveBeenCalled();
+  });
+
+  it("accepts a plain comment on a done issue even when the workspace cannot be reopened", async () => {
+    // The audit comment is not resuming anything, so a workspace that is
+    // un-reopenable must not turn it into a 409.
+    mockIssueService.getById.mockResolvedValue({ ...makeIssue(), status: "done", assigneeAgentId: null });
+    mockIssueService.addComment.mockResolvedValue({ id: "comment-1", body: "decision recorded" });
+    mockExecutionWorkspaceService.reopenClosedIsolatedExecutionWorkspaceForIssue.mockResolvedValue({
+      ok: false,
+      code: "not_reopenable",
+      message: "Execution workspace is not reopenable",
+    });
+
+    const res = await request(createApp())
+      .post(`/api/issues/${issueId}/comments`)
+      .send({ body: "decision recorded" });
+
+    expect(res.status).toBe(201);
+    expect(mockIssueService.addComment).toHaveBeenCalledTimes(1);
+  });
+
+  it("still reopens the closed workspace for a comment that resumes a done issue", async () => {
+    // `reopen: true` on a terminal issue is a resume: it needs the worktree,
+    // so the reopen still runs and still blocks when the rebuild fails.
+    mockIssueService.getById.mockResolvedValue({ ...makeIssue(), status: "done", assigneeAgentId: null });
+    mockIssueService.update.mockResolvedValue({ ...makeIssue(), status: "todo" });
+    mockIssueService.addComment.mockResolvedValue({ id: "comment-1", body: "hello" });
+
+    const res = await request(createApp())
+      .post(`/api/issues/${issueId}/comments`)
+      .send({ body: "please continue", reopen: true });
+
+    expect(mockExecutionWorkspaceService.reopenClosedIsolatedExecutionWorkspaceForIssue).toHaveBeenCalledTimes(1);
+    expect(res.status).toBe(201);
+  });
+
   it("returns 503 and blocks the checkout when the rebuild fails", async () => {
     mockExecutionWorkspaceService.reopenClosedIsolatedExecutionWorkspaceForIssue.mockResolvedValue({
       ok: false,
diff --git a/server/src/routes/issues.ts b/server/src/routes/issues.ts
index 0cc963a4e0..5ba1426b2c 100644
--- a/server/src/routes/issues.ts
+++ b/server/src/routes/issues.ts
@@ -17065,9 +17065,14 @@ export function issueRoutes(
       // blocker, and run-cap gate passes. A rejected comment must not rebuild and
       // republish the workspace as active, because the issue stays terminal and the
       // reaper then skips the leaked workspace.
+      //
+      // A comment on a terminal issue that does not resume the work is a plain
+      // record: it never needs the worktree. Rebuilding one for it would either
+      // churn a workspace the reaper immediately reaps again or block an audit
+      // comment with a 409 the workspace was never needed for.
       let reopenedWorkspace: Pick<ExecutionWorkspace, "id"> | null = null;
       let reopenedGeneration: number | null = null;
-      if (closedExecutionWorkspace) {
+      if (closedExecutionWorkspace && (!isClosed || effectiveMoveToTodoRequested)) {
         const reopenOutcome =
           await reopenClosedIssueExecutionWorkspaceOrRespond(
             req,