diff --git a/desktop/src/api/skillMarket.ts b/desktop/src/api/skillMarket.ts
new file mode 100644
index 00000000..e1416c87
--- /dev/null
+++ b/desktop/src/api/skillMarket.ts
@@ -0,0 +1,54 @@
+import { api } from './client'
+import type {
+  SkillMarketDetail,
+  SkillMarketInstallResult,
+  SkillMarketListParams,
+  SkillMarketListResponse,
+  SkillMarketSource,
+} from '../types/skillMarket'
+
+export const skillMarketApi = {
+  list: (params: SkillMarketListParams = {}) => {
+    const query = new URLSearchParams()
+    setStringParam(query, 'source', params.source)
+    setStringParam(query, 'sort', params.sort)
+    setStringParam(query, 'q', params.q)
+    if (!query.has('q')) {
+      setStringParam(query, 'query', params.query)
+    }
+    setStringParam(query, 'cursor', params.cursor)
+    if (params.limit !== undefined) {
+      query.set('limit', String(params.limit))
+    }
+
+    const suffix = query.toString() ? `?${query.toString()}` : ''
+    return api.get<SkillMarketListResponse>(`/api/skill-market${suffix}`, {
+      timeout: 30_000,
+    })
+  },
+
+  detail: (source: SkillMarketSource, slug: string) => {
+    return api.get<{ detail: SkillMarketDetail }>(
+      `/api/skill-market/${source}/${encodeURIComponent(slug)}`,
+      { timeout: 30_000 },
+    )
+  },
+
+  install: (source: SkillMarketSource, slug: string, version?: string) => {
+    const body: { source: SkillMarketSource; slug: string; version?: string } = { source, slug }
+    if (version !== undefined) {
+      body.version = version
+    }
+
+    return api.post<SkillMarketInstallResult>('/api/skill-market/install', body, {
+      timeout: 120_000,
+    })
+  },
+}
+
+function setStringParam(query: URLSearchParams, name: string, value: string | undefined): void {
+  const trimmed = value?.trim()
+  if (trimmed) {
+    query.set(name, trimmed)
+  }
+}
diff --git a/desktop/src/stores/skillMarketStore.test.ts b/desktop/src/stores/skillMarketStore.test.ts
new file mode 100644
index 00000000..e0fe375a
--- /dev/null
+++ b/desktop/src/stores/skillMarketStore.test.ts
@@ -0,0 +1,168 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import { skillMarketApi } from '../api/skillMarket'
+import type { SkillMarketDetail, SkillMarketItem } from '../types/skillMarket'
+import { useSkillMarketStore } from './skillMarketStore'
+
+vi.mock('../api/skillMarket', () => ({
+  skillMarketApi: {
+    list: vi.fn(),
+    detail: vi.fn(),
+    install: vi.fn(),
+  },
+}))
+
+const mockedSkillMarketApi = vi.mocked(skillMarketApi)
+
+function makeItem(overrides: Partial<SkillMarketItem> = {}): SkillMarketItem {
+  return {
+    source: 'clawhub',
+    sourceMode: 'primary',
+    slug: 'skill-vetter',
+    displayName: 'Skill Vetter',
+    summary: 'Security-first skill vetting.',
+    canonicalUrl: 'https://clawhub.ai/skill-vetter',
+    trustState: 'clean',
+    installed: false,
+    ...overrides,
+  }
+}
+
+function makeDetail(overrides: Partial<SkillMarketDetail> = {}): SkillMarketDetail {
+  return {
+    ...makeItem(),
+    files: [],
+    riskLabels: [],
+    installEligibility: { status: 'installable' },
+    ...overrides,
+  }
+}
+
+describe('skillMarketStore', () => {
+  beforeEach(() => {
+    vi.clearAllMocks()
+    useSkillMarketStore.setState({
+      items: [],
+      selectedDetail: null,
+      source: 'auto',
+      sort: 'downloads',
+      query: '',
+      isLoading: false,
+      isDetailLoading: false,
+      isInstalling: false,
+      error: null,
+    })
+  })
+
+  it('loads marketplace items with trimmed query parameters', async () => {
+    const item = makeItem()
+    mockedSkillMarketApi.list.mockResolvedValue({
+      items: [item],
+      nextCursor: null,
+      source: 'clawhub',
+      sourceStatus: 'ok',
+    })
+    useSkillMarketStore.setState({
+      source: 'skillhub',
+      sort: 'trending',
+      query: '  vetter  ',
+    })
+
+    await useSkillMarketStore.getState().fetchItems()
+
+    expect(mockedSkillMarketApi.list).toHaveBeenCalledWith({
+      source: 'skillhub',
+      sort: 'trending',
+      q: 'vetter',
+    })
+    expect(useSkillMarketStore.getState().items).toEqual([item])
+    expect(useSkillMarketStore.getState().isLoading).toBe(false)
+    expect(useSkillMarketStore.getState().error).toBeNull()
+  })
+
+  it('sets an error when loading marketplace items fails', async () => {
+    mockedSkillMarketApi.list.mockRejectedValue(new Error('market unavailable'))
+
+    await useSkillMarketStore.getState().fetchItems()
+
+    expect(useSkillMarketStore.getState().items).toEqual([])
+    expect(useSkillMarketStore.getState().isLoading).toBe(false)
+    expect(useSkillMarketStore.getState().error).toBe('market unavailable')
+  })
+
+  it('updates source, sort, and query filters', () => {
+    useSkillMarketStore.getState().setSource('clawhub')
+    useSkillMarketStore.getState().setSort('updated')
+    useSkillMarketStore.getState().setQuery('security')
+
+    expect(useSkillMarketStore.getState().source).toBe('clawhub')
+    expect(useSkillMarketStore.getState().sort).toBe('updated')
+    expect(useSkillMarketStore.getState().query).toBe('security')
+  })
+
+  it('loads selected marketplace detail', async () => {
+    const detail = makeDetail()
+    mockedSkillMarketApi.detail.mockResolvedValue({ detail })
+
+    await useSkillMarketStore.getState().fetchDetail('clawhub', 'skill-vetter')
+
+    expect(mockedSkillMarketApi.detail).toHaveBeenCalledWith('clawhub', 'skill-vetter')
+    expect(useSkillMarketStore.getState().selectedDetail).toEqual(detail)
+    expect(useSkillMarketStore.getState().isDetailLoading).toBe(false)
+    expect(useSkillMarketStore.getState().error).toBeNull()
+  })
+
+  it('installs selected detail and refreshes the list and detail', async () => {
+    const selected = makeDetail({ version: '1.0.0' })
+    const refreshed = makeDetail({
+      installed: true,
+      installEligibility: { status: 'installed', installedSkillName: 'skill-vetter' },
+    })
+    mockedSkillMarketApi.install.mockResolvedValue({
+      installed: true,
+      skillName: 'skill-vetter',
+      targetPath: '/Users/nanmi/.claude/skills/skill-vetter',
+    })
+    mockedSkillMarketApi.list.mockResolvedValue({
+      items: [makeItem({ installed: true })],
+      nextCursor: null,
+      source: 'clawhub',
+      sourceStatus: 'ok',
+    })
+    mockedSkillMarketApi.detail.mockResolvedValue({ detail: refreshed })
+    useSkillMarketStore.setState({ selectedDetail: selected })
+
+    await useSkillMarketStore.getState().installSelected()
+
+    expect(mockedSkillMarketApi.install).toHaveBeenCalledWith('clawhub', 'skill-vetter', '1.0.0')
+    expect(mockedSkillMarketApi.list).toHaveBeenCalledWith({
+      source: 'auto',
+      sort: 'downloads',
+      q: undefined,
+    })
+    expect(mockedSkillMarketApi.detail).toHaveBeenCalledWith('clawhub', 'skill-vetter')
+    expect(useSkillMarketStore.getState().selectedDetail).toEqual(refreshed)
+    expect(useSkillMarketStore.getState().isInstalling).toBe(false)
+  })
+
+  it('does not call install APIs when no detail is selected', async () => {
+    await useSkillMarketStore.getState().installSelected()
+
+    expect(mockedSkillMarketApi.install).not.toHaveBeenCalled()
+    expect(mockedSkillMarketApi.list).not.toHaveBeenCalled()
+    expect(mockedSkillMarketApi.detail).not.toHaveBeenCalled()
+    expect(useSkillMarketStore.getState().isInstalling).toBe(false)
+  })
+
+  it('sets an error when installing selected detail fails', async () => {
+    useSkillMarketStore.setState({ selectedDetail: makeDetail() })
+    mockedSkillMarketApi.install.mockRejectedValue(new Error('install failed'))
+
+    await useSkillMarketStore.getState().installSelected()
+
+    expect(mockedSkillMarketApi.install).toHaveBeenCalledWith('clawhub', 'skill-vetter', undefined)
+    expect(mockedSkillMarketApi.list).not.toHaveBeenCalled()
+    expect(mockedSkillMarketApi.detail).not.toHaveBeenCalled()
+    expect(useSkillMarketStore.getState().isInstalling).toBe(false)
+    expect(useSkillMarketStore.getState().error).toBe('install failed')
+  })
+})
diff --git a/desktop/src/stores/skillMarketStore.ts b/desktop/src/stores/skillMarketStore.ts
new file mode 100644
index 00000000..821b303c
--- /dev/null
+++ b/desktop/src/stores/skillMarketStore.ts
@@ -0,0 +1,99 @@
+import { create } from 'zustand'
+import { skillMarketApi } from '../api/skillMarket'
+import type {
+  SkillMarketDetail,
+  SkillMarketItem,
+  SkillMarketListSource,
+  SkillMarketSort,
+  SkillMarketSource,
+} from '../types/skillMarket'
+
+type SkillMarketStore = {
+  items: SkillMarketItem[]
+  selectedDetail: SkillMarketDetail | null
+  source: SkillMarketListSource
+  sort: SkillMarketSort
+  query: string
+  isLoading: boolean
+  isDetailLoading: boolean
+  isInstalling: boolean
+  error: string | null
+  setSource: (source: SkillMarketListSource) => void
+  setSort: (sort: SkillMarketSort) => void
+  setQuery: (query: string) => void
+  fetchItems: () => Promise<void>
+  fetchDetail: (source: SkillMarketSource, slug: string) => Promise<void>
+  installSelected: () => Promise<void>
+  clearDetail: () => void
+}
+
+export const useSkillMarketStore = create<SkillMarketStore>((set, get) => ({
+  items: [],
+  selectedDetail: null,
+  source: 'auto',
+  sort: 'downloads',
+  query: '',
+  isLoading: false,
+  isDetailLoading: false,
+  isInstalling: false,
+  error: null,
+
+  setSource: (source) => set({ source }),
+  setSort: (sort) => set({ sort }),
+  setQuery: (query) => set({ query }),
+
+  fetchItems: async () => {
+    const { source, sort, query } = get()
+    set({ isLoading: true, error: null })
+    try {
+      const result = await skillMarketApi.list({
+        source,
+        sort,
+        q: query.trim() || undefined,
+      })
+      set({ items: result.items, isLoading: false })
+    } catch (err) {
+      set({
+        isLoading: false,
+        error: getErrorMessage(err),
+      })
+    }
+  },
+
+  fetchDetail: async (source, slug) => {
+    set({ isDetailLoading: true, error: null })
+    try {
+      const { detail } = await skillMarketApi.detail(source, slug)
+      set({ selectedDetail: detail, isDetailLoading: false })
+    } catch (err) {
+      set({
+        isDetailLoading: false,
+        error: getErrorMessage(err),
+      })
+    }
+  },
+
+  installSelected: async () => {
+    const detail = get().selectedDetail
+    if (!detail) return
+
+    set({ isInstalling: true, error: null })
+    try {
+      await skillMarketApi.install(detail.source, detail.slug, detail.version)
+      await get().fetchItems()
+      await get().fetchDetail(detail.source, detail.slug)
+      set({ isInstalling: false })
+    } catch (err) {
+      set({
+        isInstalling: false,
+        error: getErrorMessage(err),
+      })
+    }
+  },
+
+  clearDetail: () => set({ selectedDetail: null }),
+}))
+
+function getErrorMessage(err: unknown): string {
+  return err instanceof Error ? err.message : String(err)
+}
diff --git a/desktop/src/types/skillMarket.ts b/desktop/src/types/skillMarket.ts
new file mode 100644
index 00000000..258019cc
--- /dev/null
+++ b/desktop/src/types/skillMarket.ts
@@ -0,0 +1,86 @@
+export type SkillMarketSource = 'clawhub' | 'skillhub'
+export type SkillMarketListSource = 'auto' | SkillMarketSource
+export type SkillMarketSourceMode = 'primary' | 'fallback' | 'enhanced'
+export type SkillMarketTrustState =
+  | 'clean'
+  | 'benign'
+  | 'signed'
+  | 'official'
+  | 'warning'
+  | 'unknown'
+  | 'blocked'
+
+export type SkillMarketRiskLabel =
+  | 'allowed-tools'
+  | 'hooks'
+  | 'scripts'
+  | 'executables'
+  | 'external-network'
+  | 'requires-api-key'
+
+export type SkillMarketSort = 'downloads' | 'installs' | 'stars' | 'updated' | 'trending'
+
+export type SkillMarketItem = {
+  source: SkillMarketSource
+  sourceMode: SkillMarketSourceMode
+  slug: string
+  displayName: string
+  summary: string
+  summaryZh?: string
+  owner?: string
+  canonicalUrl: string
+  upstreamUrl?: string
+  license?: string | null
+  version?: string
+  downloads?: number
+  installs?: number
+  stars?: number
+  category?: string
+  tags?: string[]
+  requiresApiKey?: boolean
+  trustState: SkillMarketTrustState
+  trustSummary?: string
+  installed: boolean
+}
+
+export type SkillMarketFile = {
+  path: string
+  size?: number
+  sha256?: string
+}
+
+export type SkillMarketInstallEligibility =
+  | { status: 'installable' }
+  | { status: 'installed'; installedSkillName: string }
+  | { status: 'conflict'; targetPath: string }
+  | { status: 'blocked'; reason: string }
+
+export type SkillMarketDetail = SkillMarketItem & {
+  files: SkillMarketFile[]
+  entryPreview?: string
+  riskLabels: SkillMarketRiskLabel[]
+  installEligibility: SkillMarketInstallEligibility
+}
+
+export type SkillMarketListResponse = {
+  items: SkillMarketItem[]
+  nextCursor: string | null
+  source: SkillMarketSource
+  sourceStatus: 'ok' | 'fallback' | 'cached'
+  message?: string
+}
+
+export type SkillMarketInstallResult = {
+  installed: true
+  skillName: string
+  targetPath: string
+}
+
+export type SkillMarketListParams = {
+  source?: SkillMarketListSource
+  sort?: SkillMarketSort
+  q?: string
+  query?: string
+  cursor?: string
+  limit?: number
+}