diff --git a/src/auto-reply/reply/dispatch-from-config.ts b/src/auto-reply/reply/dispatch-from-config.ts
index 47b4209af85..835519e0cdc 100644
--- a/src/auto-reply/reply/dispatch-from-config.ts
+++ b/src/auto-reply/reply/dispatch-from-config.ts
@@ -106,6 +106,9 @@ export async function dispatchReplyFromConfig(params: {
   const sessionKey = ctx.SessionKey;
   const startTime = diagnosticsEnabled ? Date.now() : 0;
   const canTrackSession = diagnosticsEnabled && Boolean(sessionKey);
+  const isGroup = Boolean(ctx.GroupSubject || ctx.GroupChannel);
+  const groupId =
+    ctx.From?.includes(":group:") || ctx.From?.includes(":channel:") ? ctx.From : undefined;
 
   const recordProcessed = (
     outcome: "completed" | "skipped" | "error",
@@ -291,6 +294,8 @@ export async function dispatchReplyFromConfig(params: {
       cfg,
       abortSignal,
       mirror,
+      isGroup,
+      groupId,
     });
     if (!result.ok) {
       logVerbose(`dispatch-from-config: route-reply failed: ${result.error ?? "unknown error"}`);
@@ -316,6 +321,8 @@ export async function dispatchReplyFromConfig(params: {
           accountId: ctx.AccountId,
           threadId: ctx.MessageThreadId,
           cfg,
+          isGroup,
+          groupId,
         });
         queuedFinal = result.ok;
         if (result.ok) {
@@ -499,6 +506,8 @@ export async function dispatchReplyFromConfig(params: {
           accountId: ctx.AccountId,
           threadId: ctx.MessageThreadId,
           cfg,
+          isGroup,
+          groupId,
         });
         if (!result.ok) {
           logVerbose(
@@ -549,6 +558,8 @@ export async function dispatchReplyFromConfig(params: {
               accountId: ctx.AccountId,
               threadId: ctx.MessageThreadId,
               cfg,
+              isGroup,
+              groupId,
             });
             queuedFinal = result.ok || queuedFinal;
             if (result.ok) {
diff --git a/src/auto-reply/reply/route-reply.ts b/src/auto-reply/reply/route-reply.ts
index e349c31e542..1c620d6e3ef 100644
--- a/src/auto-reply/reply/route-reply.ts
+++ b/src/auto-reply/reply/route-reply.ts
@@ -37,6 +37,10 @@ export type RouteReplyParams = {
   abortSignal?: AbortSignal;
   /** Mirror reply into session transcript (default: true when sessionKey is set). */
   mirror?: boolean;
+  /** Whether this message is being sent in a group/channel context */
+  isGroup?: boolean;
+  /** Group or channel identifier for correlation with received events */
+  groupId?: string;
 };
 
 export type RouteReplyResult = {
@@ -145,6 +149,8 @@ export async function routeReply(params: RouteReplyParams): Promise<RouteReplyRe
               agentId: resolvedAgentId,
               text,
               mediaUrls,
+              ...(params.isGroup != null ? { isGroup: params.isGroup } : {}),
+              ...(params.groupId ? { groupId: params.groupId } : {}),
             }
           : undefined,
     });
diff --git a/src/hooks/internal-hooks.ts b/src/hooks/internal-hooks.ts
index 70c6a06ccf2..4a29acb8bbe 100644
--- a/src/hooks/internal-hooks.ts
+++ b/src/hooks/internal-hooks.ts
@@ -85,6 +85,10 @@ export type MessageSentHookContext = {
   conversationId?: string;
   /** Message ID returned by the provider */
   messageId?: string;
+  /** Whether this message was sent in a group/channel context */
+  isGroup?: boolean;
+  /** Group or channel identifier, if applicable */
+  groupId?: string;
 };
 
 export type MessageSentHookEvent = InternalHookEvent & {
diff --git a/src/infra/outbound/deliver.ts b/src/infra/outbound/deliver.ts
index 6cc52c71b9b..c578656d3e4 100644
--- a/src/infra/outbound/deliver.ts
+++ b/src/infra/outbound/deliver.ts
@@ -220,6 +220,10 @@ type DeliverOutboundPayloadsCoreParams = {
     agentId?: string;
     text?: string;
     mediaUrls?: string[];
+    /** Whether this message is being sent in a group/channel context */
+    isGroup?: boolean;
+    /** Group or channel identifier for correlation with received events */
+    groupId?: string;
   };
   silent?: boolean;
 };
@@ -478,6 +482,8 @@ async function deliverOutboundPayloadsCore(
     });
   const hookRunner = getGlobalHookRunner();
   const sessionKeyForInternalHooks = params.mirror?.sessionKey ?? params.session?.key;
+  const mirrorIsGroup = params.mirror?.isGroup;
+  const mirrorGroupId = params.mirror?.groupId;
   if (
     hookRunner?.hasHooks("message_sent") &&
     params.session?.agentId &&
@@ -534,6 +540,8 @@ async function deliverOutboundPayloadsCore(
           accountId: accountId ?? undefined,
           conversationId: to,
           messageId: params.messageId,
+          ...(mirrorIsGroup != null ? { isGroup: mirrorIsGroup } : {}),
+          ...(mirrorGroupId ? { groupId: mirrorGroupId } : {}),
         }),
       ).catch(() => {});
     };