diff --git a/lib/controllers/compose.js b/lib/controllers/compose.js
index c916a60..e69e115 100644
--- a/lib/controllers/compose.js
+++ b/lib/controllers/compose.js
@@ -1,10 +1,39 @@
 /**
- * Compose controllers — reply form via Micropub.
+ * Compose controllers — reply form via Micropub (public) or native AP (direct).
  */
 
+import { Create, Note, Mention } from "@fedify/fedify/vocab";
 import { getToken, validateToken } from "../csrf.js";
 import { sanitizeContent } from "../timeline-store.js";
 
+function createPublicationAwareDocumentLoader(documentLoader, publicationUrl) {
+  if (typeof documentLoader !== "function") {
+    return documentLoader;
+  }
+
+  let publicationHost = "";
+  try {
+    publicationHost = new URL(publicationUrl).hostname;
+  } catch {
+    return documentLoader;
+  }
+
+  return (url, options = {}) => {
+    try {
+      const parsed = new URL(
+        typeof url === "string" ? url : (url?.href || String(url)),
+      );
+      if (parsed.hostname === publicationHost) {
+        return documentLoader(url, { ...options, allowPrivateAddress: true });
+      }
+    } catch {
+      // Fall through to default loader behavior.
+    }
+
+    return documentLoader(url, options);
+  };
+}
+
 /**
  * Fetch syndication targets from the Micropub config endpoint.
  * @param {object} application - Indiekit application locals
@@ -76,9 +105,13 @@ export function composeController(mountPath, plugin) {
               { handle, publicationUrl: plugin._publicationUrl },
             );
             // Use authenticated document loader for Authorized Fetch
-            const documentLoader = await ctx.getDocumentLoader({
+            const rawDocumentLoader = await ctx.getDocumentLoader({
               identifier: handle,
             });
+            const documentLoader = createPublicationAwareDocumentLoader(
+              rawDocumentLoader,
+              plugin._publicationUrl,
+            );
             const remoteObject = await ctx.lookupObject(new URL(replyTo), {
               documentLoader,
             });
@@ -135,6 +168,23 @@ export function composeController(mountPath, plugin) {
         target.defaultChecked = name === "@rick@rmendes.net" || name === "@rmendes.net";
       }
 
+      // Check if this is a direct/private message reply by looking at notification metadata
+      let isDirect = false;
+      let senderActorUrl = "";
+      if (replyTo) {
+        const ap_notifications = application?.collections?.get("ap_notifications");
+        if (ap_notifications) {
+          const notif = await ap_notifications.findOne({
+            $or: [{ uid: replyTo }, { url: replyTo }],
+            isDirect: true,
+          });
+          if (notif) {
+            isDirect = true;
+            senderActorUrl = notif.senderActorUrl || notif.actorUrl || "";
+          }
+        }
+      }
+
       const csrfToken = getToken(request.session);
 
       response.render("activitypub-compose", {
@@ -143,6 +193,8 @@ export function composeController(mountPath, plugin) {
         replyTo,
         replyContext,
         syndicationTargets,
+        isDirect,
+        senderActorUrl,
         csrfToken,
         mountPath,
       });
@@ -171,6 +223,8 @@ export function submitComposeController(mountPath, plugin) {
       const { content } = request.body;
       const inReplyTo = request.body["in-reply-to"];
       const syndicateTo = request.body["mp-syndicate-to"];
+      const isDirect = request.body["is-direct"] === "true";
+      const senderActorUrl = request.body["sender-actor-url"] || "";
 
       if (!content || !content.trim()) {
         return response.status(400).render("error", {
@@ -179,7 +233,65 @@ export function submitComposeController(mountPath, plugin) {
         });
       }
 
-      // Post as blog reply via Micropub
+      // --- Native AP path for direct/private replies ---
+      if (isDirect && senderActorUrl && plugin._federation) {
+        try {
+          const handle = plugin.options.actor.handle;
+          const ctx = plugin._federation.createContext(
+            new URL(plugin._publicationUrl),
+            { handle, publicationUrl: plugin._publicationUrl },
+          );
+
+          const actorUri = ctx.getActorUri(handle);
+          const uuid = crypto.randomUUID();
+          const noteId = new URL(
+            `${plugin._publicationUrl.replace(/\/$/, "")}/activitypub/notes/${uuid}`,
+          );
+
+          const note = new Note({
+            id: noteId,
+            attributedTo: actorUri,
+            to: new URL(senderActorUrl),
+            content: content.trim(),
+            ...(inReplyTo ? { replyTarget: new URL(inReplyTo) } : {}),
+            tag: new Mention({ href: new URL(senderActorUrl) }),
+          });
+
+          const create = new Create({
+            id: new URL(`${noteId.href}#create`),
+            actor: actorUri,
+            to: new URL(senderActorUrl),
+            object: note,
+          });
+
+          // Resolve recipient for delivery
+          const { resolveAuthor } = await import("../resolve-author.js");
+          const documentLoader = await ctx.getDocumentLoader({ identifier: handle });
+          const recipient = await resolveAuthor(
+            senderActorUrl,
+            ctx,
+            documentLoader,
+            application?.collections,
+          );
+
+          if (recipient) {
+            await ctx.sendActivity({ identifier: handle }, recipient, create, {
+              orderingKey: noteId.href,
+            });
+            console.info(`[ActivityPub] Sent direct AP reply to ${senderActorUrl}`);
+          }
+
+          return response.redirect(`${mountPath}/admin/reader/notifications`);
+        } catch (error) {
+          console.error("[ActivityPub] Native AP DM reply failed:", error.message);
+          return response.status(500).render("error", {
+            title: "Error",
+            content: "Failed to send direct reply. Please try again later.",
+          });
+        }
+      }
+
+      // --- Public reply path via Micropub ---
       const micropubEndpoint = application.micropubEndpoint;
 
       if (!micropubEndpoint) {
diff --git a/lib/controllers/reader.js b/lib/controllers/reader.js
index f330276..b6160fc 100644
--- a/lib/controllers/reader.js
+++ b/lib/controllers/reader.js
@@ -117,7 +117,7 @@ export function readerController(mountPath) {
 }
 
 export function notificationsController(mountPath) {
-  const validTabs = ["all", "reply", "like", "boost", "follow"];
+  const validTabs = ["all", "reply", "mention", "like", "boost", "follow"];
 
   return async (request, response, next) => {
     try {
diff --git a/lib/inbox-listeners.js b/lib/inbox-listeners.js
index a8839e7..101756b 100644
--- a/lib/inbox-listeners.js
+++ b/lib/inbox-listeners.js
@@ -454,6 +454,14 @@ export function registerInboxListeners(inboxChain, options) {
         const tags = Array.isArray(object.tag) ? object.tag : [object.tag];
         const ourActorUrl = ctx.getActorUri(handle).href;
 
+        // Detect direct/private visibility: no public collection in `to` or `cc`
+        const PUBLIC_COLLECTION = "https://www.w3.org/ns/activitystreams#Public";
+        const toHrefs = (object.toIds || []).map((u) => u?.href || String(u));
+        const ccHrefs = (object.ccIds || []).map((u) => u?.href || String(u));
+        const isDirect =
+          !toHrefs.includes(PUBLIC_COLLECTION) &&
+          !ccHrefs.includes(PUBLIC_COLLECTION);
+
         for (const tag of tags) {
           if (tag.type === "Mention" && tag.href?.href === ourActorUrl) {
             const actorInfo = await extractActorInfo(actorObj, { documentLoader: authLoader });
@@ -469,6 +477,8 @@ export function registerInboxListeners(inboxChain, options) {
               actorName: actorInfo.name,
               actorPhoto: actorInfo.photo,
               actorHandle: actorInfo.handle,
+              isDirect,
+              senderActorUrl: actorInfo.url,
               content: {
                 text: contentText,
                 html: mentionHtml,
diff --git a/lib/storage/notifications.js b/lib/storage/notifications.js
index ce6cd85..80d8b3d 100644
--- a/lib/storage/notifications.js
+++ b/lib/storage/notifications.js
@@ -64,9 +64,9 @@ export async function getNotifications(collections, options = {}) {
 
   // Type filter
   if (options.type) {
-    // "reply" tab shows both replies and mentions
+    // "reply" tab shows replies only; mentions have their own "mention" tab
     if (options.type === "reply") {
-      query.type = { $in: ["reply", "mention"] };
+      query.type = "reply";
     } else {
       query.type = options.type;
     }
@@ -126,11 +126,13 @@ export async function getNotificationCountsByType(collections, unreadOnly = fals
 
   const results = await ap_notifications.aggregate(pipeline).toArray();
 
-  const counts = { all: 0, reply: 0, like: 0, boost: 0, follow: 0 };
+  const counts = { all: 0, reply: 0, mention: 0, like: 0, boost: 0, follow: 0 };
   for (const { _id, count } of results) {
     counts.all += count;
-    if (_id === "reply" || _id === "mention") {
+    if (_id === "reply") {
       counts.reply += count;
+    } else if (_id === "mention") {
+      counts.mention += count;
     } else if (counts[_id] !== undefined) {
       counts[_id] = count;
     }
diff --git a/views/activitypub-compose.njk b/views/activitypub-compose.njk
index c1783fb..85ec4ab 100644
--- a/views/activitypub-compose.njk
+++ b/views/activitypub-compose.njk
@@ -21,11 +21,21 @@
     </div>
   {% endif %}
 
+  {% if isDirect %}
+    <div class="ap-compose__dm-notice">
+      🔒 {{ __("activitypub.compose.directNotice") if __("activitypub.compose.directNotice") != "activitypub.compose.directNotice" else "Direct message — reply stays private" }}
+    </div>
+  {% endif %}
+
   <form method="post" action="{{ mountPath }}/admin/reader/compose" class="ap-compose__form">
     <input type="hidden" name="_csrf" value="{{ csrfToken }}">
     {% if replyTo %}
       <input type="hidden" name="in-reply-to" value="{{ replyTo }}">
     {% endif %}
+    {% if isDirect %}
+      <input type="hidden" name="is-direct" value="true">
+      <input type="hidden" name="sender-actor-url" value="{{ senderActorUrl }}">
+    {% endif %}
 
     {# Content textarea #}
     <div class="ap-compose__editor">
@@ -35,8 +45,8 @@
         required></textarea>
     </div>
 
-    {# Syndication targets #}
-    {% if syndicationTargets.length > 0 %}
+    {# Syndication targets — hidden for direct messages #}
+    {% if syndicationTargets.length > 0 and not isDirect %}
       <fieldset class="ap-compose__syndication">
         <legend>{{ __("activitypub.compose.syndicateLabel") }}</legend>
         {% for target in syndicationTargets %}
@@ -50,9 +60,13 @@
 
     <div class="ap-compose__actions">
       <button type="submit" class="ap-compose__submit">
-        {{ __("activitypub.compose.submitMicropub") }}
+        {% if isDirect %}
+          🔒 {{ __("activitypub.compose.submitDirect") if __("activitypub.compose.submitDirect") != "activitypub.compose.submitDirect" else "Send direct reply" }}
+        {% else %}
+          {{ __("activitypub.compose.submitMicropub") }}
+        {% endif %}
       </button>
-      <a href="{{ mountPath }}/admin/reader" class="ap-compose__cancel">
+      <a href="{{ mountPath }}/admin/reader/notifications" class="ap-compose__cancel">
         {{ __("activitypub.compose.cancel") }}
       </a>
     </div>
diff --git a/views/activitypub-notifications.njk b/views/activitypub-notifications.njk
index d7beebf..03c7459 100644
--- a/views/activitypub-notifications.njk
+++ b/views/activitypub-notifications.njk
@@ -11,6 +11,10 @@
       {{ __("activitypub.notifications.tabs.replies") }}
       {% if tabCounts.reply %}<span class="ap-tab__count">{{ tabCounts.reply }}</span>{% endif %}
     </a>
+    <a href="{{ notifBase }}?tab=mention" class="ap-tab{% if tab == 'mention' %} ap-tab--active{% endif %}">
+      🔒 {{ __("activitypub.notifications.tabs.direct") if __("activitypub.notifications.tabs.direct") != "activitypub.notifications.tabs.direct" else "Direct" }}
+      {% if tabCounts.mention %}<span class="ap-tab__count">{{ tabCounts.mention }}</span>{% endif %}
+    </a>
     <a href="{{ notifBase }}?tab=like" class="ap-tab{% if tab == 'like' %} ap-tab--active{% endif %}">
       {{ __("activitypub.notifications.tabs.likes") }}
       {% if tabCounts.like %}<span class="ap-tab__count">{{ tabCounts.like }}</span>{% endif %}
diff --git a/views/partials/ap-notification-card.njk b/views/partials/ap-notification-card.njk
index c64d12f..a2df9ff 100644
--- a/views/partials/ap-notification-card.njk
+++ b/views/partials/ap-notification-card.njk
@@ -1,6 +1,6 @@
 {# Notification card partial #}
 
-<div class="ap-notification{% if not item.read %} ap-notification--unread{% endif %}">
+<div class="ap-notification{% if not item.read %} ap-notification--unread{% endif %}{% if item.isDirect %} ap-notification--direct{% endif %}">
   {# Dismiss button #}
   <form method="post" action="{{ mountPath }}/admin/reader/notifications/delete" class="ap-notification__dismiss">
     <input type="hidden" name="_csrf" value="{{ csrfToken }}">
@@ -18,7 +18,7 @@
       <span class="ap-notification__avatar ap-notification__avatar--default" aria-hidden="true">{{ item.actorName[0] | upper if item.actorName else "?" }}</span>
     {% endif %}
     <span class="ap-notification__type-badge">
-      {% if item.type == "like" %}❤{% elif item.type == "boost" %}🔁{% elif item.type == "follow" %}👤{% elif item.type == "reply" %}💬{% elif item.type == "mention" %}@{% endif %}
+      {% if item.type == "like" %}❤{% elif item.type == "boost" %}🔁{% elif item.type == "follow" %}👤{% elif item.type == "reply" %}💬{% elif item.type == "mention" %}{% if item.isDirect %}🔒{% else %}@{% endif %}{% endif %}
     </span>
   </div>