diff --git a/js/ui.js b/js/ui.js
index 96aae8a..4b7d51e 100644
--- a/js/ui.js
+++ b/js/ui.js
@@ -483,17 +483,20 @@ function _renderJobConfigFields(key, cfg) {
       <input class="form-input" id="job-cfg-api-key" type="password"
         placeholder="tskey-api-…" value="${esc(cfg.api_key ?? '')}">
     </div>`;
-  if (key === 'patchmon_sync') return `
+  if (key === 'patchmon_sync' || key === 'semaphore_sync') {
+    const label = key === 'semaphore_sync' ? 'API Token (Bearer)' : 'API Token (Basic)';
+    return `
     <div class="form-group">
       <label class="form-label" for="job-cfg-api-url">API URL</label>
       <input class="form-input" id="job-cfg-api-url" type="text"
-        placeholder="http://patchmon:3000/api/v1/api/hosts" value="${esc(cfg.api_url ?? '')}">
+        value="${esc(cfg.api_url ?? '')}">
     </div>
     <div class="form-group">
-      <label class="form-label" for="job-cfg-api-token">API Token (Basic)</label>
+      <label class="form-label" for="job-cfg-api-token">${label}</label>
       <input class="form-input" id="job-cfg-api-token" type="password"
-        placeholder="Basic token…" value="${esc(cfg.api_token ?? '')}">
+        value="${esc(cfg.api_token ?? '')}">
     </div>`;
+  }
   return '';
 }
 
diff --git a/server/db.js b/server/db.js
index 660f654..c0d0fd5 100644
--- a/server/db.js
+++ b/server/db.js
@@ -125,6 +125,10 @@ function seedJobs() {
   upsert.run('patchmon_sync', 'Patchmon Sync',
     'Syncs Patchmon host registration status to instances by matching hostnames.',
     0, 60, JSON.stringify({ api_url: 'http://patchmon:3000/api/v1/api/hosts', api_token: '' }));
+
+  upsert.run('semaphore_sync', 'Semaphore Sync',
+    'Syncs Semaphore inventory membership to instances by matching hostnames.',
+    0, 60, JSON.stringify({ api_url: 'http://semaphore:3000/api/project/1/inventory/1', api_token: '' }));
 }
 
 // ── Queries ───────────────────────────────────────────────────────────────────
diff --git a/server/jobs.js b/server/jobs.js
index cd2070b..cfcb20e 100644
--- a/server/jobs.js
+++ b/server/jobs.js
@@ -66,11 +66,46 @@ async function patchmonSyncHandler(cfg) {
   return { summary: `${updated} updated of ${instances.length}` };
 }
 
+// ── Semaphore Sync ────────────────────────────────────────────────────────────
+
+async function semaphoreSyncHandler(cfg) {
+  const { api_url, api_token } = cfg;
+  if (!api_url || !api_token) throw new Error('Semaphore not configured — set API URL and token');
+
+  const res = await fetch(api_url, {
+    headers: { Authorization: `Bearer ${api_token}` },
+  });
+  if (!res.ok) throw new Error(`Semaphore API ${res.status}`);
+
+  const data = await res.json();
+  // Inventory is an Ansible INI string; extract bare hostnames
+  const hostSet = new Set(
+    (data.inventory ?? '').split('\n')
+      .map(l => l.trim())
+      .filter(l => l && !l.startsWith('[') && !l.startsWith('#') && !l.startsWith(';'))
+      .map(l => l.split(/[\s=]/)[0])
+      .filter(Boolean)
+  );
+
+  const instances = getInstances();
+  let updated = 0;
+  for (const inst of instances) {
+    const newSemaphore = hostSet.has(inst.name) ? 1 : 0;
+    if (newSemaphore !== inst.semaphore) {
+      const { id: _id, created_at: _ca, updated_at: _ua, ...instData } = inst;
+      updateInstance(inst.vmid, { ...instData, semaphore: newSemaphore });
+      updated++;
+    }
+  }
+  return { summary: `${updated} updated of ${instances.length}` };
+}
+
 // ── Registry ──────────────────────────────────────────────────────────────────
 
 const HANDLERS = {
-  tailscale_sync: tailscaleSyncHandler,
-  patchmon_sync:  patchmonSyncHandler,
+  tailscale_sync:  tailscaleSyncHandler,
+  patchmon_sync:   patchmonSyncHandler,
+  semaphore_sync:  semaphoreSyncHandler,
 };
 
 // ── Public API ────────────────────────────────────────────────────────────────
diff --git a/tests/api.test.js b/tests/api.test.js
index 7654980..3cb7f1c 100644
--- a/tests/api.test.js
+++ b/tests/api.test.js
@@ -585,4 +585,21 @@ describe('POST /api/jobs/:id/run', () => {
     const res = await request(app).post(`/api/jobs/${id}/run`)
     expect(res.status).toBe(500)
   })
+
+  it('semaphore_sync: parses ansible inventory and updates instances', async () => {
+    const semaphoreJob = {
+      key: 'semaphore_sync', name: 'Semaphore Sync', description: 'test',
+      enabled: 0, schedule: 60,
+      config: JSON.stringify({ api_url: 'http://semaphore:3000/api/project/1/inventory/1', api_token: 'bearer-token' }),
+    }
+    createJob(semaphoreJob)
+    const id = (await request(app).get('/api/jobs')).body[0].id
+    vi.stubGlobal('fetch', vi.fn().mockResolvedValueOnce({
+      ok: true,
+      json: async () => ({ inventory: '[production]\nplex\nhomeassistant\n' }),
+    }))
+    const res = await request(app).post(`/api/jobs/${id}/run`)
+    expect(res.status).toBe(200)
+    expect(res.body.summary).toMatch(/updated of/)
+  })
 })