diff --git a/lib/client.js b/lib/client.js
index 0b6bba5..5a5cfd2 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -621,7 +621,10 @@ async function fetchKbStatus(call, signal) {
   return unconfiguredKbSnapshot();
 }
 async function resolveKbPath(call, path, signal) {
-  const result = await call(NETXOPS_RPC_CHANNEL2, KB_RESOLVE_ENDPOINT, { path }, signal);
+  let result = await call(NETXOPS_RPC_CHANNEL2, KB_RESOLVE_ENDPOINT, { path }, signal);
+  if (!(result !== null && typeof result === "object" && result.ok === true)) {
+    result = await call(NETXOPS_RPC_CHANNEL2, KB_RESOLVE_ENDPOINT, { args: { path } }, signal);
+  }
   if (result !== null && typeof result === "object" && result.ok === true) {
     return asKbSnapshot(result.value);
   }
@@ -1376,7 +1379,7 @@ function NetxopsCard(props) {
                   /* @__PURE__ */ jsx_runtime.jsx("button", {
                     type: "button",
                     className: "dsh-nx-btn",
-                    disabled: disabled || !state.kbDirectoryPickerReady,
+                    disabled,
                     onClick: () => {
                       props.browseKbRoot();
                     },
@@ -1388,6 +1391,15 @@ function NetxopsCard(props) {
                 className: state.kbRoot.invalid ? "dsh-nx-invalid" : "dsh-nx-hint",
                 children: state.kbRoot.invalid ? t("invalid") : state.kbDirectoryPickerReady ? t("kbRootHint") : t("kbBrowseUnavailable")
               }),
+              /* @__PURE__ */ jsx_runtime.jsx("p", {
+                className: "dsh-nx-hint",
+                children: t("kbSaveHint")
+              }),
+              state.kbUiError ? /* @__PURE__ */ jsx_runtime.jsx("p", {
+                className: "dsh-nx-invalid",
+                role: "status",
+                children: fillTemplate(t("kbBrowseFailed"), { detail: state.kbUiError })
+              }) : null,
               state.kbStatus?.status === "error" && state.kbStatus.errorMessage ? /* @__PURE__ */ jsx_runtime.jsx("p", {
                 className: "dsh-nx-invalid",
                 role: "status",
@@ -1806,6 +1818,7 @@ class NetxopsCardController {
   kbDirectoryPicker;
   kbBrowseInFlight = false;
   kbStatusInFlight = false;
+  kbUiError = null;
   imDeliveryCatalog = { ...EMPTY_IM_DELIVERY_CATALOG };
   sessionsExportStatus = null;
   sessionsExportBusy = false;
@@ -2002,17 +2015,57 @@ class NetxopsCardController {
     } catch {}
   }
   browseKbRoot() {
-    const picker = this.kbDirectoryPicker;
-    if (picker === undefined || this.kbBrowseInFlight)
+    if (this.kbBrowseInFlight)
       return;
     this.kbBrowseInFlight = true;
-    picker.pick().then((path) => {
-      if (typeof path === "string" && path.trim() !== "") {
-        this.form.actions().edit("kbRoot", path);
-        this.refreshKbPreview();
+    this.kbUiError = null;
+    this.store.set(this.projection());
+    const applyPath = (path) => {
+      if (typeof path !== "string" || path.trim() === "") {
+        return;
       }
-    }).catch(() => {}).finally(() => {
+      this.form.actions().edit("kbRoot", path.trim());
+      this.refreshKbPreview();
+    };
+    const fail = (error) => {
+      this.kbUiError = error instanceof Error ? error.message : String(error);
+      this.store.set(this.projection());
+    };
+    const picker = this.kbDirectoryPicker;
+    if (picker !== undefined) {
+      picker.pick().then(applyPath).catch(fail).finally(() => {
+        this.kbBrowseInFlight = false;
+        this.store.set(this.projection());
+      });
+      return;
+    }
+    const call = this.rpcCall;
+    if (call === undefined) {
       this.kbBrowseInFlight = false;
+      this.kbUiError = "directory picker unavailable — paste an absolute folder path and Save";
+      this.store.set(this.projection());
+      return;
+    }
+    call("/api", "directoryPicker/pick", { args: {} }).then((result) => {
+      if (typeof result === "string" || result === null) {
+        applyPath(result);
+        return;
+      }
+      if (result !== null && typeof result === "object") {
+        const row = result;
+        if (row.ok === false) {
+          fail(row.error?.message || "directoryPicker/pick failed");
+          return;
+        }
+        if ("value" in row) {
+          applyPath(row.value);
+          return;
+        }
+      }
+      applyPath(result);
+    }).catch(fail).finally(() => {
+      this.kbBrowseInFlight = false;
+      this.store.set(this.projection());
     });
   }
   exportAllSessions() {
@@ -2071,7 +2124,8 @@ class NetxopsCardController {
       apiTokenRemoteReady: this.credential.remoteReady,
       alarmPushStatus: this.alarmPushStatus,
       kbStatus: this.kbPreview ?? this.kbStatus,
-      kbDirectoryPickerReady: this.kbDirectoryPicker !== undefined,
+      kbDirectoryPickerReady: this.kbDirectoryPicker !== undefined || this.rpcCall !== undefined,
+      kbUiError: this.kbUiError,
       imDeliveryCatalog: this.imDeliveryCatalog,
       sessionsExportStatus: this.sessionsExportStatus,
       sessionsExportBusy: this.sessionsExportBusy,
@@ -2185,7 +2239,9 @@ var en = {
   kbRoot: "Package root",
   kbRootHint: "Folder with MANIFEST.json (operator-subset v1.0). Empty = pure netx.",
   kbBrowse: "Browse…",
-  kbBrowseUnavailable: "Directory picker unavailable — paste an absolute path.",
+  kbBrowseUnavailable: "Directory picker unavailable — paste an absolute folder path, then Save.",
+  kbBrowseFailed: "Browse failed: {detail}",
+  kbSaveHint: "Click Save after choosing a path to apply the knowledge base.",
   kbStatusConfigured: "Knowledge base: {operator} ({country}) v{version}",
   kbStatusUnconfigured: "Knowledge base: not configured (pure netx)",
   kbStatusError: "Knowledge base: error — {detail}",
@@ -2255,7 +2311,9 @@ var zh = {
   kbRoot: "知识包根目录",
   kbRootHint: "含 MANIFEST.json 的运营商子集包（v1.0）。留空=纯 netx。",
   kbBrowse: "浏览…",
-  kbBrowseUnavailable: "目录选择器不可用 — 请粘贴绝对路径。",
+  kbBrowseUnavailable: "目录选择器不可用 — 请粘贴绝对目录路径后点保存。",
+  kbBrowseFailed: "浏览失败：{detail}",
+  kbSaveHint: "选好路径后请点「保存」，知识库才会生效。",
   kbStatusConfigured: "知识库: {operator}（{country}） v{version}",
   kbStatusUnconfigured: "知识库: 未配置（纯 netx）",
   kbStatusError: "知识库: 错误 — {detail}",
@@ -2350,13 +2408,16 @@ function apply(ctx) {
       card.setAlarmPushRpc(undefined);
     }, "netxops: clear alarm-push rpc");
   });
-  ctx.inject(["remote.directoryPicker"], (dpCtx) => {
-    const picker = dpCtx.remote?.directoryPicker;
-    if (!picker || typeof picker.pick !== "function") {
-      dpCtx.logger.warn("netxops: remote.directoryPicker.pick unavailable — browse button disabled");
+  const bindDirectoryPicker = (picker) => {
+    if (!picker || typeof picker.pick !== "function")
       return;
-    }
     card.setDirectoryPicker(picker);
+  };
+  bindDirectoryPicker(ctx.remote?.directoryPicker);
+  ctx.inject(["remote.directoryPicker"], (dpCtx) => {
+    const viaGet = typeof dpCtx.get === "function" ? dpCtx.get("remote.directoryPicker") : undefined;
+    const viaNested = dpCtx.remote?.directoryPicker;
+    bindDirectoryPicker(viaGet ?? viaNested);
     dpCtx.effect(() => () => {
       card.setDirectoryPicker(undefined);
     }, "netxops: clear directory picker");
diff --git a/lib/index.js b/lib/index.js
index 3ea7653..dec5043 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -844,7 +844,7 @@ function registerKbContextSkill(ctx, snapshot) {
 
 // src/netx/kb-manifest.ts
 import { existsSync as existsSync2, readdirSync, readFileSync, statSync } from "node:fs";
-import { dirname as dirname2, join as join3, resolve } from "node:path";
+import { basename, dirname as dirname2, join as join3, resolve } from "node:path";
 var EMPTY_CONTENT = {
   regions: false,
   theory: false,
@@ -1000,11 +1000,26 @@ function resolveKbRoot(kbRoot, maxDepth = 3) {
   const trimmed = kbRoot.trim();
   if (!trimmed)
     return unconfiguredKbSnapshot();
-  const located = findManifest(trimmed, maxDepth);
+  let root = resolve(trimmed);
+  try {
+    const st = statSync(root);
+    if (st.isFile()) {
+      if (basename(root).toLowerCase() === "manifest.json") {
+        root = dirname2(root);
+      } else {
+        return errorSnapshot(`kbRoot is not a directory: ${root}`);
+      }
+    } else if (!st.isDirectory()) {
+      return errorSnapshot(`kbRoot is not a directory: ${root}`);
+    }
+  } catch {
+    return errorSnapshot(`kbRoot not found: ${root}`);
+  }
+  const located = findManifest(root, maxDepth);
   if (located.error)
     return errorSnapshot(located.error);
   if (located.paths.length === 0) {
-    return errorSnapshot(`no MANIFEST.json under ${resolve(trimmed)} (maxDepth=${maxDepth})`);
+    return errorSnapshot(`no MANIFEST.json under ${root} (maxDepth=${maxDepth})`);
   }
   if (located.paths.length > 1) {
     return errorSnapshot(`ambiguous MANIFEST.json (${located.paths.length} hits); pick a unique package root`);
diff --git a/src/client/NetxopsCard.tsx b/src/client/NetxopsCard.tsx
index de4e630..734bb44 100644
--- a/src/client/NetxopsCard.tsx
+++ b/src/client/NetxopsCard.tsx
@@ -521,7 +521,7 @@ export function NetxopsCard(props: NetxopsCardProps) {
             <button
               type="button"
               className="dsh-nx-btn"
-              disabled={disabled || !state.kbDirectoryPickerReady}
+              disabled={disabled}
               onClick={() => { props.browseKbRoot() }}
             >
               {t('kbBrowse')}
@@ -534,6 +534,14 @@ export function NetxopsCard(props: NetxopsCardProps) {
                 ? t('kbRootHint')
                 : t('kbBrowseUnavailable')}
           </p>
+          <p className="dsh-nx-hint">{t('kbSaveHint')}</p>
+          {state.kbUiError
+            ? (
+              <p className="dsh-nx-invalid" role="status">
+                {fillTemplate(t('kbBrowseFailed'), { detail: state.kbUiError })}
+              </p>
+            )
+            : null}
           {state.kbStatus?.status === 'error' && state.kbStatus.errorMessage
             ? <p className="dsh-nx-invalid" role="status">{state.kbStatus.errorMessage}</p>
             : null}
diff --git a/src/client/controller.ts b/src/client/controller.ts
index e5e4fca..101812d 100644
--- a/src/client/controller.ts
+++ b/src/client/controller.ts
@@ -91,6 +91,8 @@ export interface NetxopsCardState extends CardShell {
   kbStatus: KbSnapshot | null
   /** Soft-injected `remote.directoryPicker` is available. */
   kbDirectoryPickerReady: boolean
+  /** Last browse / resolve UI error (picker refuse, RPC miss, …). */
+  kbUiError: string | null
   /** Saved IM delivery targets for the picker (soft-depends on dsh-im-ops). */
   imDeliveryCatalog: ImDeliveryCatalog
   /** Bulk session-export readiness from Host RPC; null when RPC is absent. */
@@ -143,6 +145,7 @@ export class NetxopsCardController {
   private kbDirectoryPicker: DirectoryPickerRemote | undefined
   private kbBrowseInFlight = false
   private kbStatusInFlight = false
+  private kbUiError: string | null = null
   private imDeliveryCatalog: ImDeliveryCatalog = { ...EMPTY_IM_DELIVERY_CATALOG }
   private sessionsExportStatus: SessionsExportStatus | null = null
   private sessionsExportBusy = false
@@ -400,24 +403,73 @@ export class NetxopsCardController {
   }
 
   /**
-   * Open the Host OS directory chooser and write the path into kbRoot.
+   * Open the Host OS directory chooser (or /api directoryPicker/pick fallback)
+   * and write the path into kbRoot.
    */
   browseKbRoot(): void {
-    const picker = this.kbDirectoryPicker
-    if (picker === undefined || this.kbBrowseInFlight) return
+    if (this.kbBrowseInFlight) return
     this.kbBrowseInFlight = true
-    void picker.pick()
-      .then((path) => {
-        if (typeof path === 'string' && path.trim() !== '') {
-          this.form.actions().edit('kbRoot', path)
-          void this.refreshKbPreview()
+    this.kbUiError = null
+    this.store.set(this.projection())
+
+    const applyPath = (path: unknown): void => {
+      if (typeof path !== 'string' || path.trim() === '') {
+        // Cancel / empty — no error
+        return
+      }
+      this.form.actions().edit('kbRoot', path.trim())
+      void this.refreshKbPreview()
+    }
+
+    const fail = (error: unknown): void => {
+      this.kbUiError = error instanceof Error ? error.message : String(error)
+      this.store.set(this.projection())
+    }
+
+    const picker = this.kbDirectoryPicker
+    if (picker !== undefined) {
+      void picker.pick()
+        .then(applyPath)
+        .catch(fail)
+        .finally(() => {
+          this.kbBrowseInFlight = false
+          this.store.set(this.projection())
+        })
+      return
+    }
+
+    // Fallback: workspace controller remote verb on the Host /api channel.
+    const call = this.rpcCall
+    if (call === undefined) {
+      this.kbBrowseInFlight = false
+      this.kbUiError = 'directory picker unavailable — paste an absolute folder path and Save'
+      this.store.set(this.projection())
+      return
+    }
+    void call('/api', 'directoryPicker/pick', { args: {} })
+      .then((result) => {
+        // Remotes often return the path directly, or { ok, value }.
+        if (typeof result === 'string' || result === null) {
+          applyPath(result)
+          return
         }
+        if (result !== null && typeof result === 'object') {
+          const row = result as { ok?: boolean; value?: unknown; error?: { message?: string } }
+          if (row.ok === false) {
+            fail(row.error?.message || 'directoryPicker/pick failed')
+            return
+          }
+          if ('value' in row) {
+            applyPath(row.value)
+            return
+          }
+        }
+        applyPath(result)
       })
-      .catch(() => {
-        // Picker cancel / host refusal — leave draft unchanged.
-      })
+      .catch(fail)
       .finally(() => {
         this.kbBrowseInFlight = false
+        this.store.set(this.projection())
       })
   }
 
@@ -482,7 +534,8 @@ export class NetxopsCardController {
       apiTokenRemoteReady: this.credential.remoteReady,
       alarmPushStatus: this.alarmPushStatus,
       kbStatus: this.kbPreview ?? this.kbStatus,
-      kbDirectoryPickerReady: this.kbDirectoryPicker !== undefined,
+      kbDirectoryPickerReady: this.kbDirectoryPicker !== undefined || this.rpcCall !== undefined,
+      kbUiError: this.kbUiError,
       imDeliveryCatalog: this.imDeliveryCatalog,
       sessionsExportStatus: this.sessionsExportStatus,
       sessionsExportBusy: this.sessionsExportBusy,
diff --git a/src/client/index.ts b/src/client/index.ts
index 02d809d..d38eb29 100644
--- a/src/client/index.ts
+++ b/src/client/index.ts
@@ -79,14 +79,24 @@ export function apply(ctx: ClientContext): void {
   })
 
   // Soft-inject Host directory picker for knowledge-base browse.
+  // Prefer the dedicated remote namespace; also accept ctx.remote.directoryPicker.
+  const bindDirectoryPicker = (picker: { pick?: (signal?: AbortSignal) => Promise<string | null> } | undefined): void => {
+    if (!picker || typeof picker.pick !== 'function') return
+    card.setDirectoryPicker(picker as { pick: (signal?: AbortSignal) => Promise<string | null> })
+  }
+  bindDirectoryPicker(
+    (ctx as { remote?: { directoryPicker?: { pick?: (signal?: AbortSignal) => Promise<string | null> } } })
+      .remote?.directoryPicker,
+  )
   ctx.inject(['remote.directoryPicker'], (dpCtx) => {
-    const picker = (dpCtx as { remote?: { directoryPicker?: { pick?: (signal?: AbortSignal) => Promise<string | null> } } })
+    const viaGet = typeof (dpCtx as { get?: (name: string) => unknown }).get === 'function'
+      ? (dpCtx as { get: (name: string) => unknown }).get('remote.directoryPicker') as
+        | { pick?: (signal?: AbortSignal) => Promise<string | null> }
+        | undefined
+      : undefined
+    const viaNested = (dpCtx as { remote?: { directoryPicker?: { pick?: (signal?: AbortSignal) => Promise<string | null> } } })
       .remote?.directoryPicker
-    if (!picker || typeof picker.pick !== 'function') {
-      dpCtx.logger.warn('netxops: remote.directoryPicker.pick unavailable — browse button disabled')
-      return
-    }
-    card.setDirectoryPicker(picker)
+    bindDirectoryPicker(viaGet ?? viaNested)
     dpCtx.effect(() => () => {
       card.setDirectoryPicker(undefined)
     }, 'netxops: clear directory picker')
diff --git a/src/client/kb-status-view.ts b/src/client/kb-status-view.ts
index c55b13f..11a3318 100644
--- a/src/client/kb-status-view.ts
+++ b/src/client/kb-status-view.ts
@@ -64,7 +64,11 @@ export async function resolveKbPath(
   path: string,
   signal?: AbortSignal,
 ): Promise<KbSnapshot> {
-  const result = await call(NETXOPS_RPC_CHANNEL, KB_RESOLVE_ENDPOINT, { path }, signal)
+  // Prefer flat `{ path }` (netxops channel); also try `{ args: { path } }`.
+  let result = await call(NETXOPS_RPC_CHANNEL, KB_RESOLVE_ENDPOINT, { path }, signal)
+  if (!(result !== null && typeof result === 'object' && (result as { ok?: boolean }).ok === true)) {
+    result = await call(NETXOPS_RPC_CHANNEL, KB_RESOLVE_ENDPOINT, { args: { path } }, signal)
+  }
   if (result !== null && typeof result === 'object' && (result as { ok?: boolean }).ok === true) {
     return asKbSnapshot((result as { value?: unknown }).value)
   }
diff --git a/src/client/locales.ts b/src/client/locales.ts
index ee57bef..51a5464 100644
--- a/src/client/locales.ts
+++ b/src/client/locales.ts
@@ -23,6 +23,8 @@ export type NetxopsLocaleKey =
   | 'kbRootHint'
   | 'kbBrowse'
   | 'kbBrowseUnavailable'
+  | 'kbBrowseFailed'
+  | 'kbSaveHint'
   | 'kbStatusConfigured'
   | 'kbStatusUnconfigured'
   | 'kbStatusError'
@@ -92,7 +94,9 @@ export const en: Record<NetxopsLocaleKey, string> = {
   kbRoot: 'Package root',
   kbRootHint: 'Folder with MANIFEST.json (operator-subset v1.0). Empty = pure netx.',
   kbBrowse: 'Browse…',
-  kbBrowseUnavailable: 'Directory picker unavailable — paste an absolute path.',
+  kbBrowseUnavailable: 'Directory picker unavailable — paste an absolute folder path, then Save.',
+  kbBrowseFailed: 'Browse failed: {detail}',
+  kbSaveHint: 'Click Save after choosing a path to apply the knowledge base.',
   kbStatusConfigured: 'Knowledge base: {operator} ({country}) v{version}',
   kbStatusUnconfigured: 'Knowledge base: not configured (pure netx)',
   kbStatusError: 'Knowledge base: error — {detail}',
@@ -163,7 +167,9 @@ export const zh: Record<NetxopsLocaleKey, string> = {
   kbRoot: '知识包根目录',
   kbRootHint: '含 MANIFEST.json 的运营商子集包（v1.0）。留空=纯 netx。',
   kbBrowse: '浏览…',
-  kbBrowseUnavailable: '目录选择器不可用 — 请粘贴绝对路径。',
+  kbBrowseUnavailable: '目录选择器不可用 — 请粘贴绝对目录路径后点保存。',
+  kbBrowseFailed: '浏览失败：{detail}',
+  kbSaveHint: '选好路径后请点「保存」，知识库才会生效。',
   kbStatusConfigured: '知识库: {operator}（{country}） v{version}',
   kbStatusUnconfigured: '知识库: 未配置（纯 netx）',
   kbStatusError: '知识库: 错误 — {detail}',
diff --git a/src/netx/kb-manifest.ts b/src/netx/kb-manifest.ts
index d251f9e..08011cb 100644
--- a/src/netx/kb-manifest.ts
+++ b/src/netx/kb-manifest.ts
@@ -12,7 +12,7 @@
  */
 
 import { existsSync, readdirSync, readFileSync, statSync } from 'node:fs'
-import { dirname, join, resolve } from 'node:path'
+import { basename, dirname, join, resolve } from 'node:path'
 
 /** Known content flags; unknown keys are preserved when boolean. */
 export interface KbContentFlags {
@@ -218,15 +218,32 @@ export function parseManifest(raw: string): {
 
 /**
  * Resolve kbRoot → KbSnapshot (unconfigured / configured / error).
+ * Accepts a directory, or a path directly to MANIFEST.json (uses its parent).
  */
 export function resolveKbRoot(kbRoot: string, maxDepth = 3): KbSnapshot {
   const trimmed = kbRoot.trim()
   if (!trimmed) return unconfiguredKbSnapshot()
 
-  const located = findManifest(trimmed, maxDepth)
+  let root = resolve(trimmed)
+  try {
+    const st = statSync(root)
+    if (st.isFile()) {
+      if (basename(root).toLowerCase() === 'manifest.json') {
+        root = dirname(root)
+      } else {
+        return errorSnapshot(`kbRoot is not a directory: ${root}`)
+      }
+    } else if (!st.isDirectory()) {
+      return errorSnapshot(`kbRoot is not a directory: ${root}`)
+    }
+  } catch {
+    return errorSnapshot(`kbRoot not found: ${root}`)
+  }
+
+  const located = findManifest(root, maxDepth)
   if (located.error) return errorSnapshot(located.error)
   if (located.paths.length === 0) {
-    return errorSnapshot(`no MANIFEST.json under ${resolve(trimmed)} (maxDepth=${maxDepth})`)
+    return errorSnapshot(`no MANIFEST.json under ${root} (maxDepth=${maxDepth})`)
   }
   if (located.paths.length > 1) {
     return errorSnapshot(
diff --git a/test/kb-manifest.test.mjs b/test/kb-manifest.test.mjs
index bf3aef3..9fdfd98 100644
--- a/test/kb-manifest.test.mjs
+++ b/test/kb-manifest.test.mjs
@@ -144,8 +144,31 @@ test('findManifest respects maxDepth', () => {
   })
 })
 
-test('missing kbRoot path → error', () => {
-  const snap = resolveKbRoot(join(tmpdir(), 'netxops-kb-missing-' + Date.now()))
-  assert.equal(snap.status, 'error')
-  assert.match(snap.errorMessage, /not found/)
+test('path to MANIFEST.json file resolves via parent dir', () => {
+  withTemp((root) => {
+    const manifestPath = join(root, 'MANIFEST.json')
+    writeFileSync(manifestPath, validManifest(), 'utf8')
+    const snap = resolveKbRoot(manifestPath)
+    assert.equal(snap.status, 'configured')
+    assert.equal(snap.realRoot, root)
+    assert.equal(snap.operatorName, 'IOH')
+  })
+})
+
+test('contract content flags hasRegions etc. are accepted', () => {
+  withTemp((root) => {
+    writeFileSync(join(root, 'MANIFEST.json'), validManifest({
+      content: {
+        hasRegions: true,
+        hasTheory: true,
+        hasPacket: true,
+        hasCommon: true,
+        hasSkills: true,
+      },
+    }), 'utf8')
+    const snap = resolveKbRoot(root)
+    assert.equal(snap.status, 'configured')
+    assert.equal(snap.content.hasRegions, true)
+    assert.equal(snap.content.hasSkills, true)
+  })
 })