diff --git a/src/AcDream.Core.Net/Messages/InventoryActions.cs b/src/AcDream.Core.Net/Messages/InventoryActions.cs
new file mode 100644
index 0000000..f46bd5b
--- /dev/null
+++ b/src/AcDream.Core.Net/Messages/InventoryActions.cs
@@ -0,0 +1,133 @@
+using System.Buffers.Binary;
+
+namespace AcDream.Core.Net.Messages;
+
+/// <summary>
+/// Outbound inventory-manipulation GameActions: stack merge/split, give,
+/// drop, shortcuts. All ride in the <c>0xF7B1</c> GameAction envelope.
+///
+/// <para>
+/// References: r08 §3 rows 0x0054-0x0056 / 0x019B-0x019D / 0x00CD.
+/// </para>
+/// </summary>
+public static class InventoryActions
+{
+    public const uint GameActionEnvelope = 0xF7B1u;
+
+    public const uint StackableMergeOpcode          = 0x0054u;
+    public const uint StackableSplitToContainerOpcode = 0x0055u;
+    public const uint StackableSplitTo3DOpcode      = 0x0056u;
+    public const uint StackableSplitToWieldOpcode   = 0x019Bu;
+    public const uint GiveObjectRequestOpcode       = 0x00CDu;
+    public const uint AddShortcutOpcode             = 0x019Cu;
+    public const uint RemoveShortcutOpcode          = 0x019Du;
+    public const uint TeleToPoiOpcode               = 0x00B1u;
+
+    /// <summary>
+    /// Merge stack A into stack B of the same item type. Server validates
+    /// compatibility; if the merge fails it rolls back via
+    /// InventoryServerSaveFailed (0x00A0).
+    /// </summary>
+    public static byte[] BuildStackableMerge(uint seq, uint mergeFromGuid, uint mergeToGuid, uint amount)
+    {
+        byte[] body = new byte[24];
+        BinaryPrimitives.WriteUInt32LittleEndian(body,            GameActionEnvelope);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(4),  seq);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(8),  StackableMergeOpcode);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(12), mergeFromGuid);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(16), mergeToGuid);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(20), amount);
+        return body;
+    }
+
+    /// <summary>Split N items off a stack into a container at placement.</summary>
+    public static byte[] BuildStackableSplitToContainer(
+        uint seq, uint stackGuid, uint containerGuid, uint placement, uint amount)
+    {
+        byte[] body = new byte[28];
+        BinaryPrimitives.WriteUInt32LittleEndian(body,            GameActionEnvelope);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(4),  seq);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(8),  StackableSplitToContainerOpcode);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(12), stackGuid);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(16), containerGuid);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(20), placement);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(24), amount);
+        return body;
+    }
+
+    /// <summary>Split N items off a stack and drop them on the ground.</summary>
+    public static byte[] BuildStackableSplitTo3D(uint seq, uint stackGuid, uint amount)
+    {
+        byte[] body = new byte[20];
+        BinaryPrimitives.WriteUInt32LittleEndian(body,            GameActionEnvelope);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(4),  seq);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(8),  StackableSplitTo3DOpcode);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(12), stackGuid);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(16), amount);
+        return body;
+    }
+
+    /// <summary>Split N items off a stack into an equip slot.</summary>
+    public static byte[] BuildStackableSplitToWield(
+        uint seq, uint stackGuid, uint equipLocation, uint amount)
+    {
+        byte[] body = new byte[24];
+        BinaryPrimitives.WriteUInt32LittleEndian(body,            GameActionEnvelope);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(4),  seq);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(8),  StackableSplitToWieldOpcode);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(12), stackGuid);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(16), equipLocation);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(20), amount);
+        return body;
+    }
+
+    /// <summary>Give an item (or a stack of N) to a target creature/NPC.</summary>
+    public static byte[] BuildGiveObjectRequest(
+        uint seq, uint targetGuid, uint itemGuid, uint amount)
+    {
+        byte[] body = new byte[24];
+        BinaryPrimitives.WriteUInt32LittleEndian(body,            GameActionEnvelope);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(4),  seq);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(8),  GiveObjectRequestOpcode);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(12), targetGuid);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(16), itemGuid);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(20), amount);
+        return body;
+    }
+
+    /// <summary>Pin an item / spell to a quickbar slot.</summary>
+    public static byte[] BuildAddShortcut(
+        uint seq, uint slotIndex, uint objectType, uint targetId)
+    {
+        byte[] body = new byte[24];
+        BinaryPrimitives.WriteUInt32LittleEndian(body,            GameActionEnvelope);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(4),  seq);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(8),  AddShortcutOpcode);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(12), slotIndex);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(16), objectType);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(20), targetId);
+        return body;
+    }
+
+    /// <summary>Unpin a quickbar slot.</summary>
+    public static byte[] BuildRemoveShortcut(uint seq, uint slotIndex)
+    {
+        byte[] body = new byte[16];
+        BinaryPrimitives.WriteUInt32LittleEndian(body,            GameActionEnvelope);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(4),  seq);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(8),  RemoveShortcutOpcode);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(12), slotIndex);
+        return body;
+    }
+
+    /// <summary>Teleport to a Point of Interest (quest-driven recall).</summary>
+    public static byte[] BuildTeleToPoi(uint seq, uint poiId)
+    {
+        byte[] body = new byte[16];
+        BinaryPrimitives.WriteUInt32LittleEndian(body,            GameActionEnvelope);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(4),  seq);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(8),  TeleToPoiOpcode);
+        BinaryPrimitives.WriteUInt32LittleEndian(body.AsSpan(12), poiId);
+        return body;
+    }
+}
diff --git a/tests/AcDream.Core.Net.Tests/Messages/InventoryActionsTests.cs b/tests/AcDream.Core.Net.Tests/Messages/InventoryActionsTests.cs
new file mode 100644
index 0000000..5bfec69
--- /dev/null
+++ b/tests/AcDream.Core.Net.Tests/Messages/InventoryActionsTests.cs
@@ -0,0 +1,109 @@
+using System;
+using System.Buffers.Binary;
+using AcDream.Core.Net.Messages;
+using Xunit;
+
+namespace AcDream.Core.Net.Tests.Messages;
+
+public sealed class InventoryActionsTests
+{
+    [Fact]
+    public void BuildStackableMerge_CarriesBothGuidsAndAmount()
+    {
+        byte[] body = InventoryActions.BuildStackableMerge(
+            seq: 1, mergeFromGuid: 0xAA, mergeToGuid: 0xBB, amount: 5);
+
+        Assert.Equal(24, body.Length);
+        Assert.Equal(InventoryActions.StackableMergeOpcode,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(8)));
+        Assert.Equal(0xAAu,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(12)));
+        Assert.Equal(0xBBu,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(16)));
+        Assert.Equal(5u,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(20)));
+    }
+
+    [Fact]
+    public void BuildStackableSplitToContainer_FourFields()
+    {
+        byte[] body = InventoryActions.BuildStackableSplitToContainer(
+            seq: 1, stackGuid: 0xAA, containerGuid: 0xBB, placement: 3, amount: 10);
+
+        Assert.Equal(28, body.Length);
+        Assert.Equal(InventoryActions.StackableSplitToContainerOpcode,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(8)));
+        Assert.Equal(3u,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(20)));
+        Assert.Equal(10u,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(24)));
+    }
+
+    [Fact]
+    public void BuildStackableSplitTo3D_TwoFields()
+    {
+        byte[] body = InventoryActions.BuildStackableSplitTo3D(
+            seq: 1, stackGuid: 0xAA, amount: 3);
+        Assert.Equal(20, body.Length);
+        Assert.Equal(InventoryActions.StackableSplitTo3DOpcode,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(8)));
+    }
+
+    [Fact]
+    public void BuildStackableSplitToWield_HasEquipLocation()
+    {
+        byte[] body = InventoryActions.BuildStackableSplitToWield(
+            seq: 1, stackGuid: 0xAA, equipLocation: 0x00400000, amount: 1);
+        Assert.Equal(0x00400000u,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(16)));
+    }
+
+    [Fact]
+    public void BuildGiveObjectRequest_TargetItemAmount()
+    {
+        byte[] body = InventoryActions.BuildGiveObjectRequest(
+            seq: 1, targetGuid: 0xAA, itemGuid: 0xBB, amount: 2);
+        Assert.Equal(InventoryActions.GiveObjectRequestOpcode,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(8)));
+        Assert.Equal(0xAAu,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(12)));
+        Assert.Equal(0xBBu,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(16)));
+        Assert.Equal(2u,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(20)));
+    }
+
+    [Fact]
+    public void BuildAddShortcut_ThreeFields()
+    {
+        byte[] body = InventoryActions.BuildAddShortcut(
+            seq: 1, slotIndex: 0, objectType: 1, targetId: 0x3E1);
+        Assert.Equal(InventoryActions.AddShortcutOpcode,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(8)));
+        Assert.Equal(0u,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(12)));
+        Assert.Equal(1u,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(16)));
+        Assert.Equal(0x3E1u,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(20)));
+    }
+
+    [Fact]
+    public void BuildRemoveShortcut_HasSlotOnly()
+    {
+        byte[] body = InventoryActions.BuildRemoveShortcut(seq: 1, slotIndex: 5);
+        Assert.Equal(16, body.Length);
+        Assert.Equal(5u,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(12)));
+    }
+
+    [Fact]
+    public void BuildTeleToPoi_SimpleIdPayload()
+    {
+        byte[] body = InventoryActions.BuildTeleToPoi(seq: 1, poiId: 42);
+        Assert.Equal(InventoryActions.TeleToPoiOpcode,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(8)));
+        Assert.Equal(42u,
+            BinaryPrimitives.ReadUInt32LittleEndian(body.AsSpan(12)));
+    }
+}