diff --git a/sidecar/.vs/Aryx.AgentHost.slnx/DesignTimeBuild/.dtbcache.v2 b/sidecar/.vs/Aryx.AgentHost.slnx/DesignTimeBuild/.dtbcache.v2
new file mode 100644
index 0000000..0a64be5
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diff --git a/sidecar/.vs/Aryx.AgentHost.slnx/FileContentIndex/c67ca173-dd43-42f7-b189-aa5b0dbe371b.vsidx b/sidecar/.vs/Aryx.AgentHost.slnx/FileContentIndex/c67ca173-dd43-42f7-b189-aa5b0dbe371b.vsidx
new file mode 100644
index 0000000..252774b
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diff --git a/sidecar/src/Aryx.AgentHost/Services/CopilotTurnExecutionState.cs b/sidecar/src/Aryx.AgentHost/Services/CopilotTurnExecutionState.cs
index 00a9835..11b05b5 100644
--- a/sidecar/src/Aryx.AgentHost/Services/CopilotTurnExecutionState.cs
+++ b/sidecar/src/Aryx.AgentHost/Services/CopilotTurnExecutionState.cs
@@ -98,7 +98,8 @@ internal sealed class CopilotTurnExecutionState
                 string toolName = toolExecutionStart.Data.ToolName.Trim();
                 ToolNamesByCallId[toolCallId] = toolName;
                 ActiveAgent = agent;
-                AgentActivityEventDto? toolActivity = CreateToolCallingActivity(agent, toolName, toolCallId);
+                AgentActivityEventDto? toolActivity = CreateToolCallingActivity(
+                    agent, toolName, toolCallId, toolExecutionStart.Data.Arguments);
                 if (toolActivity is not null)
                 {
                     _pendingEvents.Enqueue(toolActivity);
@@ -295,7 +296,8 @@ internal sealed class CopilotTurnExecutionState
     private AgentActivityEventDto? CreateToolCallingActivity(
         AgentIdentity agent,
         string toolName,
-        string toolCallId)
+        string toolCallId,
+        object? rawArguments = null)
     {
         if (toolName.StartsWith("handoff_to_", StringComparison.Ordinal))
         {
@@ -312,6 +314,7 @@ internal sealed class CopilotTurnExecutionState
             AgentName = agent.AgentName,
             ToolName = toolName,
             ToolCallId = toolCallId,
+            ToolArguments = WorkflowRequestInfoInterpreter.NormalizeRawToolArguments(rawArguments),
         };
     }
 
diff --git a/sidecar/src/Aryx.AgentHost/Services/WorkflowRequestInfoInterpreter.cs b/sidecar/src/Aryx.AgentHost/Services/WorkflowRequestInfoInterpreter.cs
index 2e99906..ec97f9f 100644
--- a/sidecar/src/Aryx.AgentHost/Services/WorkflowRequestInfoInterpreter.cs
+++ b/sidecar/src/Aryx.AgentHost/Services/WorkflowRequestInfoInterpreter.cs
@@ -205,6 +205,26 @@ internal static class WorkflowRequestInfoInterpreter
         return false;
     }
 
+    public static IReadOnlyDictionary<string, object?>? NormalizeRawToolArguments(object? rawArguments)
+    {
+        return rawArguments switch
+        {
+            null => null,
+            JsonElement { ValueKind: JsonValueKind.Object } element => NormalizeToolArgumentObject(element),
+            IEnumerable<KeyValuePair<string, object?>> dictionary => NormalizeToolArguments(dictionary),
+            _ => NormalizeRawToolArgumentsViaJson(rawArguments),
+        };
+    }
+
+    private static IReadOnlyDictionary<string, object?>? NormalizeRawToolArgumentsViaJson(object value)
+    {
+        string json = JsonSerializer.Serialize(value, value.GetType(), JsonOptions);
+        using JsonDocument document = JsonDocument.Parse(json);
+        return document.RootElement.ValueKind == JsonValueKind.Object
+            ? NormalizeToolArgumentObject(document.RootElement)
+            : null;
+    }
+
     private static IReadOnlyDictionary<string, object?>? NormalizeToolArguments(
         IEnumerable<KeyValuePair<string, object?>>? arguments)
     {
diff --git a/sidecar/tests/Aryx.AgentHost.Tests/CopilotTurnExecutionStateTests.cs b/sidecar/tests/Aryx.AgentHost.Tests/CopilotTurnExecutionStateTests.cs
index d982068..b96ecc0 100644
--- a/sidecar/tests/Aryx.AgentHost.Tests/CopilotTurnExecutionStateTests.cs
+++ b/sidecar/tests/Aryx.AgentHost.Tests/CopilotTurnExecutionStateTests.cs
@@ -68,16 +68,33 @@ public sealed class CopilotTurnExecutionStateTests
         state.ObserveSessionEvent(
             command.Workflow.GetAgentNodes()[0],
             SessionEvent.FromJson(
-                """{"type":"tool.execution_start","data":{"toolCallId":"tool-call-1","toolName":"view"},"id":"33333333-3333-3333-3333-333333333333","timestamp":"2026-03-27T00:00:00Z"}"""));
+                """{"type":"tool.execution_start","data":{"toolCallId":"tool-call-1","toolName":"view","arguments":{"path":"/src/main.ts","view_range":[10,20]}},"id":"33333333-3333-3333-3333-333333333333","timestamp":"2026-03-27T00:00:00Z"}"""));
 
         AgentActivityEventDto toolActivity = Assert.Single(state.DrainPendingEvents().OfType<AgentActivityEventDto>());
         Assert.Equal("tool-calling", toolActivity.ActivityType);
         Assert.Equal("view", toolActivity.ToolName);
         Assert.Equal("tool-call-1", toolActivity.ToolCallId);
+        Assert.NotNull(toolActivity.ToolArguments);
+        Assert.Equal("/src/main.ts", toolActivity.ToolArguments["path"]);
         Assert.True(state.ToolNamesByCallId.TryGetValue("tool-call-1", out string? toolName));
         Assert.Equal("view", toolName);
     }
 
+    [Fact]
+    public void ObserveSessionEvent_ToolExecutionStart_WithoutArguments_SetsToolArgumentsToNull()
+    {
+        RunTurnCommandDto command = CreateCommand();
+        CopilotTurnExecutionState state = new(command);
+
+        state.ObserveSessionEvent(
+            command.Workflow.GetAgentNodes()[0],
+            SessionEvent.FromJson(
+                """{"type":"tool.execution_start","data":{"toolCallId":"tool-call-1","toolName":"view"},"id":"33333333-3333-3333-3333-333333333333","timestamp":"2026-03-27T00:00:00Z"}"""));
+
+        AgentActivityEventDto toolActivity = Assert.Single(state.DrainPendingEvents().OfType<AgentActivityEventDto>());
+        Assert.Null(toolActivity.ToolArguments);
+    }
+
     [Fact]
     public void ObserveSessionEvent_ToolExecutionStart_DoesNotQueueToolActivityForHandoffTools()
     {
diff --git a/sidecar/tests/Aryx.AgentHost.Tests/WorkflowRequestInfoInterpreterTests.cs b/sidecar/tests/Aryx.AgentHost.Tests/WorkflowRequestInfoInterpreterTests.cs
index 1fd0080..c0c46c7 100644
--- a/sidecar/tests/Aryx.AgentHost.Tests/WorkflowRequestInfoInterpreterTests.cs
+++ b/sidecar/tests/Aryx.AgentHost.Tests/WorkflowRequestInfoInterpreterTests.cs
@@ -1,6 +1,7 @@
 using System.Collections;
 using System.Collections.Concurrent;
 using System.Runtime.CompilerServices;
+using System.Text.Json;
 using Aryx.AgentHost.Contracts;
 using Aryx.AgentHost.Services;
 using Microsoft.Agents.AI;
@@ -255,6 +256,35 @@ public sealed class WorkflowRequestInfoInterpreterTests
         Assert.False(requiresBoundary);
     }
 
+    [Fact]
+    public void NormalizeRawToolArguments_JsonElement_ExtractsArguments()
+    {
+        using JsonDocument doc = JsonDocument.Parse("""{"path":"/src/main.ts","view_range":[10,20]}""");
+        JsonElement element = doc.RootElement.Clone();
+
+        IReadOnlyDictionary<string, object?>? result = WorkflowRequestInfoInterpreter.NormalizeRawToolArguments(element);
+
+        Assert.NotNull(result);
+        Assert.Equal("/src/main.ts", result["path"]);
+        IReadOnlyList<object?> viewRange = Assert.IsAssignableFrom<IReadOnlyList<object?>>(result["view_range"]);
+        Assert.Equal(2, viewRange.Count);
+    }
+
+    [Fact]
+    public void NormalizeRawToolArguments_Null_ReturnsNull()
+    {
+        Assert.Null(WorkflowRequestInfoInterpreter.NormalizeRawToolArguments(null));
+    }
+
+    [Fact]
+    public void NormalizeRawToolArguments_EmptyObject_ReturnsNull()
+    {
+        using JsonDocument doc = JsonDocument.Parse("{}");
+        JsonElement element = doc.RootElement.Clone();
+
+        Assert.Null(WorkflowRequestInfoInterpreter.NormalizeRawToolArguments(element));
+    }
+
     private static RunTurnCommandDto CreateSingleAgentCommand()
         => CreateCommand("single", [CreateAgent("agent-1", "Primary")]);