diff --git a/frontend/src/stores/downloads.js b/frontend/src/stores/downloads.js
new file mode 100644
index 0000000..d95f633
--- /dev/null
+++ b/frontend/src/stores/downloads.js
@@ -0,0 +1,72 @@
+import { defineStore } from 'pinia'
+import { ref } from 'vue'
+import { useApi } from '../composables/useApi.js'
+
+export const useDownloadsStore = defineStore('downloads', () => {
+  const api = useApi()
+
+  const events = ref([])
+  const cursor = ref(null)
+  const hasMore = ref(true)
+  const filter = ref({ status: null, source_id: null, artist_id: null })
+  const selected = ref(null)
+  const loading = ref(false)
+  const error = ref(null)
+
+  function _params(extra = {}) {
+    const out = { limit: 50, ...extra }
+    if (filter.value.status) out.status = filter.value.status
+    if (filter.value.source_id != null) out.source_id = filter.value.source_id
+    if (filter.value.artist_id != null) out.artist_id = filter.value.artist_id
+    return out
+  }
+
+  async function loadFirst() {
+    loading.value = true
+    error.value = null
+    try {
+      const body = await api.get('/api/downloads', { params: _params() })
+      events.value = body
+      cursor.value = body.length ? body[body.length - 1].id : null
+      hasMore.value = body.length === 50
+    } catch (e) {
+      error.value = e
+    } finally {
+      loading.value = false
+    }
+  }
+
+  async function loadMore() {
+    if (!hasMore.value || cursor.value == null) return
+    loading.value = true
+    try {
+      const body = await api.get('/api/downloads', { params: _params({ before: cursor.value }) })
+      events.value.push(...body)
+      cursor.value = body.length ? body[body.length - 1].id : cursor.value
+      hasMore.value = body.length === 50
+    } catch (e) {
+      error.value = e
+    } finally {
+      loading.value = false
+    }
+  }
+
+  async function loadOne(id) {
+    selected.value = await api.get(`/api/downloads/${id}`)
+    return selected.value
+  }
+
+  async function applyFilter(patch) {
+    filter.value = { ...filter.value, ...patch }
+    await loadFirst()
+  }
+
+  function closeDetail() {
+    selected.value = null
+  }
+
+  return {
+    events, cursor, hasMore, filter, selected, loading, error,
+    loadFirst, loadMore, loadOne, applyFilter, closeDetail,
+  }
+})
diff --git a/frontend/src/stores/sources.js b/frontend/src/stores/sources.js
index 80ba142..1032edb 100644
--- a/frontend/src/stores/sources.js
+++ b/frontend/src/stores/sources.js
@@ -70,6 +70,20 @@ export const useSourcesStore = defineStore('sources', () => {
     return await api.get('/api/artists/autocomplete', { params: { q: query, limit } })
   }
 
+  // FC-3c: trigger a download for one source. Returns {download_event_id,status}.
+  const checkingIds = ref(new Set())
+
+  async function checkNow(id) {
+    checkingIds.value = new Set(checkingIds.value).add(id)
+    try {
+      return await api.post(`/api/sources/${id}/check`)
+    } finally {
+      const next = new Set(checkingIds.value)
+      next.delete(id)
+      checkingIds.value = next
+    }
+  }
+
   function sourcesByArtistGrouped() {
     // returns [{artist: {id,name,slug}, sources: [...]}, ...]
     const arr = byArtist.value.get(null) ?? []
@@ -92,8 +106,10 @@ export const useSourcesStore = defineStore('sources', () => {
   return {
     byArtist, loading, error,
     allSources,
+    checkingIds,
     loadAll, loadForArtist,
     create, update, remove,
+    checkNow,
     findOrCreateArtist, autocompleteArtist,
     sourcesByArtistGrouped,
   }
diff --git a/frontend/test/downloads.spec.js b/frontend/test/downloads.spec.js
new file mode 100644
index 0000000..a76fa90
--- /dev/null
+++ b/frontend/test/downloads.spec.js
@@ -0,0 +1,75 @@
+import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest'
+import { setActivePinia, createPinia } from 'pinia'
+import { useDownloadsStore } from '../src/stores/downloads.js'
+
+function stubFetch(handler) {
+  globalThis.fetch = vi.fn(async (url, init) => {
+    const { status, body } = handler(url, init)
+    return {
+      ok: status >= 200 && status < 300,
+      status, statusText: String(status),
+      text: async () => (body == null ? '' : JSON.stringify(body)),
+    }
+  })
+}
+
+describe('downloads store', () => {
+  beforeEach(() => setActivePinia(createPinia()))
+  afterEach(() => vi.restoreAllMocks())
+
+  it('loadFirst populates events and cursor', async () => {
+    const s = useDownloadsStore()
+    stubFetch(() => ({
+      status: 200,
+      body: [
+        { id: 10, status: 'ok', summary: {} },
+        { id: 9, status: 'error', summary: {} },
+      ],
+    }))
+    await s.loadFirst()
+    expect(s.events.map(e => e.id)).toEqual([10, 9])
+    expect(s.cursor).toBe(9)
+    expect(s.hasMore).toBe(false)
+  })
+
+  it('loadMore appends and updates cursor', async () => {
+    const s = useDownloadsStore()
+    s.events = [{ id: 10, summary: {} }, { id: 9, summary: {} }]
+    s.cursor = 9
+    s.hasMore = true
+    stubFetch(() => ({
+      status: 200,
+      body: [{ id: 8, status: 'ok', summary: {} }],
+    }))
+    await s.loadMore()
+    expect(s.events.map(e => e.id)).toEqual([10, 9, 8])
+    expect(s.cursor).toBe(8)
+  })
+
+  it('applyFilter merges and reloads', async () => {
+    const s = useDownloadsStore()
+    const urls = []
+    stubFetch((url) => {
+      urls.push(url)
+      return { status: 200, body: [] }
+    })
+    await s.applyFilter({ status: 'error' })
+    expect(s.filter.status).toBe('error')
+    expect(urls[0]).toContain('status=error')
+  })
+
+  it('loadOne populates selected', async () => {
+    const s = useDownloadsStore()
+    stubFetch(() => ({ status: 200, body: { id: 42, metadata: { run_stats: {} } } }))
+    const out = await s.loadOne(42)
+    expect(s.selected.id).toBe(42)
+    expect(out.id).toBe(42)
+  })
+
+  it('closeDetail clears selected', async () => {
+    const s = useDownloadsStore()
+    s.selected = { id: 1 }
+    s.closeDetail()
+    expect(s.selected).toBe(null)
+  })
+})
diff --git a/frontend/test/sources.spec.js b/frontend/test/sources.spec.js
index 1b15577..395ede5 100644
--- a/frontend/test/sources.spec.js
+++ b/frontend/test/sources.spec.js
@@ -78,4 +78,29 @@ describe('sources store', () => {
     expect(urls[0]).toContain('/api/artists/autocomplete')
     expect(urls[0]).toContain('q=al')
   })
+
+  it('checkNow posts to /api/sources/<id>/check', async () => {
+    const s = useSourcesStore()
+    const calls = []
+    stubFetch((url, init) => {
+      calls.push({ url, method: init?.method, body: init?.body ? JSON.parse(init.body) : null })
+      return { status: 202, body: { download_event_id: 7, status: 'pending' } }
+    })
+    const out = await s.checkNow(5)
+    expect(calls[0].url).toBe('/api/sources/5/check')
+    expect(calls[0].method).toBe('POST')
+    expect(out.download_event_id).toBe(7)
+  })
+
+  it('checkNow exposes the 409 download_event_id via error.body', async () => {
+    const s = useSourcesStore()
+    stubFetch(() => ({ status: 409, body: { download_event_id: 12, status: 'already_running' } }))
+    try {
+      await s.checkNow(5)
+    } catch (e) {
+      expect(e.body?.download_event_id).toBe(12)
+      return
+    }
+    throw new Error('Expected checkNow to throw on 409')
+  })
 })