diff --git a/src/lib/api/feed/custom.ts b/src/lib/api/feed/custom.ts
index 6f3f690..5ff27f7 100644
--- a/src/lib/api/feed/custom.ts
+++ b/src/lib/api/feed/custom.ts
@@ -52,30 +52,16 @@ export class CustomFeedAPI implements FeedAPI {
     cursor: string | undefined
     limit: number
   }): Promise<FeedAPIResponse> {
-    // Microcosm batch path: Slingshot proxies the feed generator's skeleton and
-    // fetches all post records in one request. For personalized feeds we forward
-    // a service-auth token (aud = the feed generator's DID) so the generator can
-    // identify the viewer — same as the AppView would.
-    if (MICROCOSM_ENABLED) {
+    // Microcosm batch path: Slingshot proxies the feed generator's PUBLIC
+    // skeleton and fetches all post records in one request. Slingshot's batch
+    // proxy rejects a forwarded auth token (returns 400), so we only use this
+    // path logged out. Logged-in users go through the AppView below, which
+    // forwards the viewer's auth correctly (needed for personalized feeds).
+    if (MICROCOSM_ENABLED && !this.agent.did) {
       try {
         const page = await buildCustomFeed(this.params.feed, {
-          viewerDid: this.agent.did,
           limit,
           cursor,
-          getAuthorization: this.agent.did
-            ? async (feedGenDid: string) => {
-                try {
-                  const {data} =
-                    await this.agent.com.atproto.server.getServiceAuth({
-                      aud: feedGenDid,
-                      lxm: 'app.bsky.feed.getFeedSkeleton',
-                    })
-                  return data.token
-                } catch {
-                  return undefined
-                }
-              }
-            : undefined,
         })
         if (page.feed.length) {
           return {cursor: page.cursor, feed: page.feed}