diff --git a/src/Netclaw.Actors.Tests/Channels/Contracts/SlackSessionBindingContractTests.cs b/src/Netclaw.Actors.Tests/Channels/Contracts/SlackSessionBindingContractTests.cs
index 623c15e17..defc6a63e 100644
--- a/src/Netclaw.Actors.Tests/Channels/Contracts/SlackSessionBindingContractTests.cs
+++ b/src/Netclaw.Actors.Tests/Channels/Contracts/SlackSessionBindingContractTests.cs
@@ -227,6 +227,60 @@ await AwaitAssertAsync(() =>
         }, cancellationToken: ct);
     }
 
+    [Fact]
+    public async Task Inbound_message_refreshes_active_processing_status()
+    {
+        var ct = TestContext.Current.CancellationToken;
+        var detector = new ConfigurablePromptInjectionDetector(PromptInjectionResult.Safe());
+        var sid = new SessionId("session-slack-processing-inbound-refresh");
+        var pipeline = new RecordingSessionPipeline(_ =>
+        [
+            new ProcessingStateOutput(true) { SessionId = sid }
+        ]);
+        var actor = CreateActorCore(sid, pipeline, detector);
+
+        await AwaitAssertAsync(() =>
+        {
+            var status = Assert.Single(_replyClient.Statuses);
+            Assert.Equal("is thinking...", status.Status);
+        }, cancellationToken: ct);
+
+        actor.Tell(CreateInboundMessage("new context while you are working", "user-1"));
+
+        await AwaitAssertAsync(() =>
+        {
+            Assert.NotEmpty(pipeline.CapturedInputs);
+            Assert.Collection(
+                _replyClient.Statuses,
+                status => Assert.Equal("is thinking...", status.Status),
+                status => Assert.Equal("is thinking...", status.Status));
+        }, cancellationToken: ct);
+    }
+
+    [Fact]
+    public async Task Slack_reply_refreshes_active_processing_status()
+    {
+        var ct = TestContext.Current.CancellationToken;
+        var detector = new ConfigurablePromptInjectionDetector(PromptInjectionResult.Safe());
+        var sid = new SessionId("session-slack-processing-post-refresh");
+        var pipeline = new RecordingSessionPipeline(_ =>
+        [
+            new ProcessingStateOutput(true) { SessionId = sid },
+            new TextOutput("I found the first result and am still working.") { SessionId = sid }
+        ]);
+
+        CreateActorCore(sid, pipeline, detector);
+
+        await AwaitAssertAsync(() =>
+        {
+            Assert.Contains(_replyClient.Posts, p => p.Text == "I found the first result and am still working.");
+            Assert.Collection(
+                _replyClient.Statuses,
+                status => Assert.Equal("is thinking...", status.Status),
+                status => Assert.Equal("is thinking...", status.Status));
+        }, cancellationToken: ct);
+    }
+
     [Fact]
     public async Task Processing_state_output_does_not_block_text_when_renderer_stalls()
     {
diff --git a/src/Netclaw.Channels.Discord/DiscordProcessingOutputRenderer.cs b/src/Netclaw.Channels.Discord/DiscordProcessingOutputRenderer.cs
index fb24cff91..02fac0d35 100644
--- a/src/Netclaw.Channels.Discord/DiscordProcessingOutputRenderer.cs
+++ b/src/Netclaw.Channels.Discord/DiscordProcessingOutputRenderer.cs
@@ -21,6 +21,10 @@ public async ValueTask RenderAsync(
         if (request.Output is not ProcessingStateOutput { IsProcessing: true })
             return;
 
+        // Discord typing is a transient pulse; Discord.Net documents this
+        // call as broadcasting typing for 10 seconds.
+        // https://discord.com/developers/docs/resources/channel#trigger-typing-indicator
+        // https://docs.discordnet.dev/api/Discord.IMessageChannel.html#Discord_IMessageChannel_TriggerTypingAsync_Discord_RequestOptions_
         await replyClient.TriggerTypingAsync(
             new DiscordReplyChannelId(request.Target.Destination.StableId),
             cancellationToken);
diff --git a/src/Netclaw.Channels.Slack/SlackProcessingOutputRenderer.cs b/src/Netclaw.Channels.Slack/SlackProcessingOutputRenderer.cs
index 93a6f7b58..11a70e173 100644
--- a/src/Netclaw.Channels.Slack/SlackProcessingOutputRenderer.cs
+++ b/src/Netclaw.Channels.Slack/SlackProcessingOutputRenderer.cs
@@ -29,6 +29,9 @@ public async ValueTask RenderAsync(
         if (string.IsNullOrWhiteSpace(request.Target.ThreadOrRootId))
             throw new InvalidOperationException("Slack processing indicators require a thread timestamp.");
 
+        // Slack assistant thread status is stateful: Slack clears it when the
+        // app sends a reply, after a timeout, or when an empty status is sent.
+        // https://docs.slack.dev/reference/methods/assistant.threads.setStatus/
         await replyClient.SetThreadStatusAsync(
             new SlackChannelId(request.Target.Destination.StableId),
             new SlackThreadTs(request.Target.ThreadOrRootId),
diff --git a/src/Netclaw.Channels.Slack/SlackThreadBindingActor.cs b/src/Netclaw.Channels.Slack/SlackThreadBindingActor.cs
index 32f71bf9c..bd18a387c 100644
--- a/src/Netclaw.Channels.Slack/SlackThreadBindingActor.cs
+++ b/src/Netclaw.Channels.Slack/SlackThreadBindingActor.cs
@@ -423,6 +423,8 @@ await ProcessInboundAttachmentsAsync(
                     if (_pendingCursorTs is not { } pending || ts.CompareTo(pending) > 0)
                         _pendingCursorTs = ts;
                 }
+
+                QueueProcessingIndicatorRefreshIfActive();
             }
             catch (OperationCanceledException ex)
             {
@@ -1201,6 +1203,20 @@ private void QueueProcessingIndicatorClearIfActive()
         });
     }
 
+    private void QueueProcessingIndicatorRefreshIfActive()
+    {
+        if (!_processingIndicatorActive)
+            return;
+
+        // Slack clears assistant thread status when the app sends a reply; keep
+        // long-running turns visible after Slack-side thread activity while the
+        // session still reports Processing. See SlackProcessingOutputRenderer.
+        _ = RenderProcessingStateAsync(new ProcessingStateOutput(true)
+        {
+            SessionId = _sessionId
+        });
+    }
+
     private async Task RenderProcessingStateRequestAsync(
         ChannelOutputRenderRequest request,
         bool isRequired)
@@ -1530,6 +1546,7 @@ await _dependencies.ReplyClient.PostThreadReplyAsync(new SlackPostMessage(
 
             _log.Info("Posted Slack reply message");
             ChannelTelemetry.For(ChannelType.Slack).RecordReplyPosted(_dependencies.TimeProvider.GetElapsedTime(startedAt).TotalMilliseconds);
+            QueueProcessingIndicatorRefreshIfActive();
             return PostResult.Ok;
         }
         catch (OperationCanceledException ex)