diff --git a/lith/Caddyfile b/lith/Caddyfile
--- a/lith/Caddyfile
+++ b/lith/Caddyfile
@@ -439,6 +439,14 @@ handle @duckweedprompt {
         redir https://aesthetic.computer{uri} 301
     }
 
+    # --- www.prompt.ac redirect ---
+    # (needs a proxied `www` A record in the prompt.ac zone — without it the
+    # `*.prompt.ac → 100::` Worker wildcard swallows www and 522s.)
+    @wwwpromptac host www.prompt.ac
+    handle @wwwpromptac {
+        redir https://prompt.ac{uri} 301
+    }
+
     # --- prompt.ac/menuband → menuband.app (Menu Band's own domain) ---
     # Menu Band now lives at menuband.app; this legacy path keeps working by
     # forwarding into it (subpath preserved: /menuband/privacy.html →
diff --git a/lith/DNS.md b/lith/DNS.md
--- a/lith/DNS.md
+++ b/lith/DNS.md
@@ -15,6 +15,7 @@ - `justanothersystem.org` zone: `justanothersystem.org`, `www`
 - `kidlisp.com` zone: `kidlisp.com`, `www`, `buy`, `calm`, `device`, `keep`, `keeps`, `learn`, `pj`, `top`
 - `notepat.com` zone: `notepat.com`, `www`
 - `prompt.ac` zone: `prompt.ac`, `api`, `l5`, `p5`, `papers`, `processing`, `sitemap`
+  - `www` MISSING as of 2026-07-06 — falls into the `*.prompt.ac → 100::` Worker wildcard and 522s. Fix: add `www` A → 209.38.133.33 (proxied); Caddyfile already has the www→apex redirect.
 - `quiltnet.org` zone: `quiltnet.org`, `www`
 - `sotce.net` zone: `sotce.net`, `www`