diff --git a/web/src/pages/KbSettings.test.ts b/web/src/pages/KbSettings.test.ts
new file mode 100644
index 000000000..14acde6a1
--- /dev/null
+++ b/web/src/pages/KbSettings.test.ts
@@ -0,0 +1,220 @@
+import {
+  Children, isValidElement, useState, type ChangeEvent, type ComponentProps,
+  type JSXElementConstructor, type ReactNode,
+} from "react";
+import { afterEach, beforeEach, expect, it, vi } from "vitest";
+import { api, type Kb } from "../api";
+import { S } from "../i18n";
+import { Button, Checkbox, Input, Segmented, SettingsCard } from "../ui";
+import { KbSettings } from "./KbSettings";
+
+// Node 中执行真实组件与保存回调；查询快照模拟刷新边界，不覆盖 TanStack 缓存集成。
+const hooks = vi.hoisted(() => ({
+  kbId: "kb-a",
+  data: undefined as Kb | undefined,
+  query: undefined as { queryFn: () => Promise<Kb> } | undefined,
+  invalidate: vi.fn(),
+  states: [] as unknown[],
+  dependencies: [] as Array<readonly unknown[]>,
+  effects: [] as Array<() => void>,
+  stateIndex: 0,
+  effectIndex: 0,
+  changed: false,
+  saving: undefined as Promise<unknown> | undefined,
+}));
+vi.mock("react", async (original) => ({
+  ...await original<typeof import("react")>(),
+  useState: (initial: unknown) => {
+    const index = hooks.stateIndex++;
+    if (!(index in hooks.states)) hooks.states[index] = initial;
+    return [hooks.states[index], (value: unknown) => {
+      hooks.changed ||= !Object.is(hooks.states[index], value);
+      hooks.states[index] = value;
+    }];
+  },
+  useEffect: (effect: () => void, dependencies: readonly unknown[]) => {
+    const previous = hooks.dependencies[hooks.effectIndex];
+    hooks.dependencies[hooks.effectIndex++] = dependencies;
+    if (!previous || dependencies.some((value, index) => !Object.is(value, previous[index]))) {
+      hooks.effects.push(effect);
+    }
+  },
+}));
+vi.mock("@tanstack/react-router", () => ({
+  useParams: () => ({ kbId: hooks.kbId }),
+  useNavigate: () => vi.fn(),
+}));
+vi.mock("@tanstack/react-query", () => ({
+  useQueryClient: () => ({ invalidateQueries: hooks.invalidate }),
+  useQuery: (query: { queryKey: string[]; queryFn: () => Promise<Kb> }) => {
+    if (query.queryKey[0] !== "kbOne") return { data: { failed: 0 } };
+    hooks.query = query;
+    return { data: hooks.data, isPending: !hooks.data };
+  },
+  useMutation: (options: {
+    mutationFn: (patch: Record<string, unknown>) => Promise<unknown>;
+    onSuccess: (result: unknown) => void;
+  }) => {
+    const [status, setStatus] = useState({ isPending: false, isSuccess: false });
+    return {
+      ...status,
+      mutate: (patch: Record<string, unknown>) => {
+        setStatus({ isPending: true, isSuccess: false });
+        hooks.saving = options.mutationFn(patch).then((result) => {
+          options.onSuccess(result);
+          setStatus({ isPending: false, isSuccess: true });
+        });
+      },
+    };
+  },
+}));
+
+const initial: Kb = {
+  id: "kb-a", workspace_id: "workspace", name: "Research", kind: "general",
+  description: "Original description", visibility: "open", is_default: false,
+  auto_extend_ontology: false, materialize_inferences: false,
+  auto_type_resolution: false, governance: false, governance_since: null,
+  inference_interval_minutes: 60, last_inference_at: null, ontology_lang: "en",
+};
+let server: Kb;
+
+beforeEach(() => {
+  server = { ...initial };
+  Object.assign(hooks, {
+    kbId: initial.id, data: undefined, query: undefined,
+    states: [], dependencies: [], effects: [], saving: undefined,
+  });
+  hooks.invalidate.mockReset();
+  vi.spyOn(api, "kbDetail").mockImplementation(async () => ({ ...server }));
+  vi.spyOn(api, "updateKb").mockImplementation(async (_id, patch) => {
+    server = { ...server, ...patch };
+    return server;
+  });
+});
+afterEach(() => vi.restoreAllMocks());
+
+async function refresh() {
+  render();
+  expect(hooks.query).toBeDefined();
+  hooks.data = await hooks.query!.queryFn();
+}
+
+function render(): ReactNode {
+  hooks.stateIndex = hooks.effectIndex = 0;
+  hooks.changed = false;
+  const tree = KbSettings();
+  for (const effect of hooks.effects.splice(0)) effect();
+  return hooks.changed ? render() : tree;
+}
+
+function find<P>(node: ReactNode, type: JSXElementConstructor<P> | string): P[] {
+  if (!isValidElement<{ children?: ReactNode; action?: ReactNode }>(node)) return [];
+  // JSX 的 type 与组件一致时，props 就是该组件的公开属性。
+  const matched = node.type === type ? [node.props as P] : [];
+  return [...matched, ...Children.toArray([node.props.children, node.props.action])
+    .flatMap((child) => find(child, type))];
+}
+
+function card(title: string) {
+  const found = find(render(), SettingsCard).find((item) => item.title === title);
+  expect(found, title).toBeDefined();
+  return found!;
+}
+
+function editIdentity(name: string, description: string) {
+  const inputs = find(card(S.kbset.cardIdentity).children, Input);
+  for (const [index, value] of [name, description].entries()) {
+    inputs[index].onChange!({ target: { value } } as ChangeEvent<HTMLInputElement>);
+  }
+}
+
+async function save(title: string) {
+  const button = find(card(title).action, Button)[0];
+  expect(button.disabled).toBe(false);
+  button.onClick!({} as Parameters<NonNullable<ComponentProps<typeof Button>["onClick"]>>[0]);
+  await hooks.saving;
+  expect(hooks.invalidate.mock.calls).toEqual([
+    [{ queryKey: ["kbOne", hooks.kbId] }], [{ queryKey: ["kbs"] }],
+  ]);
+  await refresh();
+}
+
+function expectSaved(title: string) {
+  const action = card(title).action;
+  expect(find(action, Button)[0].disabled).toBe(true);
+  expect(find<{ children?: ReactNode }>(action, "span")
+    .some((span) => span.children === S.kbset.saved)).toBe(true);
+}
+
+it.each(["Original description", "", null])(
+  "keeps identity drafts when only visibility is saved (description: %s)",
+  async (description) => {
+    server.description = description;
+    await refresh();
+    editIdentity("Draft name", "Draft description");
+    find(card(S.settings.kbs.visibility).children, Segmented)[0].onChange("restricted");
+    await save(S.settings.kbs.visibility);
+
+    expect(api.updateKb).toHaveBeenCalledExactlyOnceWith("kb-a", { visibility: "restricted" });
+    expect(api.kbDetail).toHaveBeenCalledTimes(2);
+    expect(find(card(S.kbset.cardIdentity).children, Input).map((input) => input.value))
+      .toEqual(["Draft name", "Draft description"]);
+    expect(find(card(S.settings.kbs.visibility).children, Segmented)[0].value).toBe("restricted");
+    expectSaved(S.settings.kbs.visibility);
+  },
+);
+
+it("synchronizes saved identity values and status while preserving other cards' drafts", async () => {
+  await refresh();
+  editIdentity("  New name  ", "  New description  ");
+  find(card(S.settings.kbs.visibility).children, Segmented)[0].onChange("restricted");
+  find(card(S.kbset.cardAutomation).children, Checkbox)[0].onChange!(true);
+  find(card(S.kbset.ontologyLang).children, Segmented)[0].onChange("zh");
+  await save(S.kbset.cardIdentity);
+
+  expect(api.updateKb).toHaveBeenLastCalledWith("kb-a", { name: "New name", description: "New description" });
+  expect(find(card(S.kbset.cardIdentity).children, Input).map((input) => input.value))
+    .toEqual(["New name", "New description"]);
+  expectSaved(S.kbset.cardIdentity);
+  expect(find(card(S.settings.kbs.visibility).children, Segmented)[0].value).toBe("restricted");
+  expect(find(card(S.kbset.cardAutomation).children, Checkbox)[0].checked).toBe(true);
+  expect(find(card(S.kbset.ontologyLang).children, Segmented)[0].value).toBe("zh");
+});
+
+it("accepts server updates on unedited cards", async () => {
+  await refresh();
+  render();
+  server = {
+    ...server, name: "Renamed remotely", description: "Updated remotely", visibility: "restricted",
+    materialize_inferences: true, auto_type_resolution: true, governance: true,
+    inference_interval_minutes: 120, ontology_lang: "zh",
+  };
+  await refresh();
+  expect(find(card(S.kbset.cardIdentity).children, Input).map((input) => input.value))
+    .toEqual([server.name, server.description]);
+  expect(find(card(S.settings.kbs.visibility).children, Segmented)[0].value).toBe("restricted");
+  expect(find(card(S.kbset.cardAutomation).children, Checkbox).map((input) => input.checked))
+    .toEqual([true, true, true]);
+  expect(find(card(S.kbset.cardAutomation).children, Input)[0].value).toBe(120);
+  expect(find(card(S.kbset.ontologyLang).children, Segmented)[0].value).toBe("zh");
+});
+
+it.each([false, true])("resets drafts when switching KB with identical server values (preloaded: %s)", async (preloaded) => {
+  await refresh();
+  editIdentity("Draft name", "Draft description");
+  find(card(S.settings.kbs.visibility).children, Segmented)[0].onChange("restricted");
+  find(card(S.kbset.cardAutomation).children, Checkbox)[0].onChange!(true);
+  find(card(S.kbset.ontologyLang).children, Segmented)[0].onChange("zh");
+  render();
+  hooks.kbId = "kb-b";
+  server = { ...initial, id: "kb-b" };
+  hooks.data = preloaded ? { ...server } : undefined;
+  render();
+  await refresh();
+  expect(find(card(S.kbset.cardIdentity).children, Input).map((input) => input.value))
+    .toEqual([initial.name, initial.description]);
+  expect(find(card(S.settings.kbs.visibility).children, Segmented)[0].value).toBe("open");
+  expect(find(card(S.kbset.cardAutomation).children, Checkbox).map((input) => input.checked))
+    .toEqual([false, false, false]);
+  expect(find(card(S.kbset.ontologyLang).children, Segmented)[0].value).toBe("en");
+});
diff --git a/web/src/pages/KbSettings.tsx b/web/src/pages/KbSettings.tsx
index 916652d45..8a30f5aad 100644
--- a/web/src/pages/KbSettings.tsx
+++ b/web/src/pages/KbSettings.tsx
@@ -125,18 +125,40 @@ export function KbSettings() {
   const [confirmingDelete, setConfirmingDelete] = useState(false);
   const [error, setError] = useState<string | null>(null);
 
+  // 每张卡只跟随自己的服务端字段；保存别的卡触发重取时，保留这张卡的草稿。
   useEffect(() => {
     if (kb.data) {
       setName(kb.data.name);
       setDesc(kb.data.description ?? "");
+    }
+  }, [kbId, kb.data?.name, kb.data?.description]);
+
+  useEffect(() => {
+    if (kb.data) {
       setVisibility(kb.data.visibility);
+    }
+  }, [kbId, kb.data?.visibility]);
+
+  useEffect(() => {
+    if (kb.data) {
       setMaterialize(kb.data.materialize_inferences);
       setAutoResolve(kb.data.auto_type_resolution);
       setGovernance(kb.data.governance);
       setInferMins(kb.data.inference_interval_minutes);
+    }
+  }, [
+    kbId,
+    kb.data?.materialize_inferences,
+    kb.data?.auto_type_resolution,
+    kb.data?.governance,
+    kb.data?.inference_interval_minutes,
+  ]);
+
+  useEffect(() => {
+    if (kb.data) {
       setOntoLang(kb.data.ontology_lang);
     }
-  }, [kb.data]);
+  }, [kbId, kb.data?.ontology_lang]);
 
   // 四张卡，四个保存：改名字那一下不该把下面的开关一起送上去
   const saveIdentity = useKbPatch(kbId!, setError);