diff --git a/admin/app/services/kiwix_catalog_service.ts b/admin/app/services/kiwix_catalog_service.ts
index e7f0422d..2d172cf3 100644
--- a/admin/app/services/kiwix_catalog_service.ts
+++ b/admin/app/services/kiwix_catalog_service.ts
@@ -24,7 +24,14 @@ import { isRawListRemoteZimFilesResponse } from '../../util/zim.js'
  * defensive — a malformed entry is skipped, never thrown.
  */
 
-const KIWIX_CATALOG_URL = 'https://browse.library.kiwix.org/catalog/v2/entries'
+// `browse.library.kiwix.org` is Kiwix's *human* browsing host. On 2026-08-29 it grew an
+// anti-crawler interstitial that answers HTTP 200 with an HTML "Please confirm..." page
+// requiring JS + a cookie, so every catalog request here returned unparseable HTML.
+// `parseZimEntries` swallows that as an empty feed, which reads as "no updates available"
+// -- a silent, permanent stall of ZIM auto-update. `opds.library.kiwix.org` is the
+// machine-facing host for the same API and is not gated; `library.kiwix.org` now 301s to
+// it. Keep catalog traffic off the browse host.
+const KIWIX_CATALOG_URL = 'https://opds.library.kiwix.org/catalog/v2/entries'
 const GITHUB_PMTILES_URL =
   'https://api.github.com/repos/Crosstalk-Solutions/project-nomad-maps/contents/pmtiles'
 
diff --git a/admin/app/services/zim_service.ts b/admin/app/services/zim_service.ts
index c8a735c2..a687c3be 100644
--- a/admin/app/services/zim_service.ts
+++ b/admin/app/services/zim_service.ts
@@ -81,7 +81,10 @@ export class ZimService {
     count: number
     query?: string
   }): Promise<ListRemoteZimFilesResponse> {
-    const LIBRARY_BASE_URL = 'https://browse.library.kiwix.org/catalog/v2/entries'
+    // The machine-facing OPDS host. NOT `browse.library.kiwix.org`, which since 2026-08-29
+    // serves an anti-crawler confirmation page (HTTP 200 + HTML) that fails
+    // `isRawListRemoteZimFilesResponse` and 500s this endpoint. See kiwix_catalog_service.
+    const LIBRARY_BASE_URL = 'https://opds.library.kiwix.org/catalog/v2/entries'
     // Kiwix returns pages of content unaware of what the user has installed locally. When
     // the installed set is large, a single 12-item Kiwix page can come back with everything
     // already installed → 0 post-filter items → frontend deadlock (#731). Accumulate across