fix: correct handoff output attribution

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

sidecar/src/Eryx.AgentHost/Services/CopilotAgentBundle.cs

@@ -56,7 +56,7 @@ internal sealed class CopilotAgentBundle : IAsyncDisposable
                 Streaming = true,
             };
 
-            if (ShouldDisableSessionTools(command.Pattern, definition, command.WorkspaceKind))
+            if (isScratchpad)
             {
                 sessionConfig.AvailableTools = [];
             }
@@ -90,25 +90,6 @@ internal sealed class CopilotAgentBundle : IAsyncDisposable
         return bundle;
     }
 
-    internal static bool ShouldDisableSessionTools(
-        PatternDefinitionDto pattern,
-        PatternAgentDefinitionDto definition,
-        string workspaceKind)
-    {
-        if (string.Equals(workspaceKind, "scratchpad", StringComparison.OrdinalIgnoreCase))
-        {
-            return true;
-        }
-
-        if (!string.Equals(pattern.Mode, "handoff", StringComparison.OrdinalIgnoreCase))
-        {
-            return false;
-        }
-
-        PatternHandoffTopology topology = PatternGraphResolver.ResolveHandoff(pattern);
-        return string.Equals(definition.Id, topology.EntryAgentId, StringComparison.OrdinalIgnoreCase);
-    }
-
     public Workflow BuildWorkflow(PatternDefinitionDto pattern)
     {
         return pattern.Mode switch

sidecar/src/Eryx.AgentHost/Services/WorkflowTranscriptProjector.cs

@@ -30,14 +30,20 @@ internal static class WorkflowTranscriptProjector
         AgentIdentity? fallbackAgent = null)
     {
         List<ChatMessageDto> mapped = [];
-        int segmentIndex = 0;
         int fallbackOutputIndex = 0;
         string createdAt = DateTimeOffset.UtcNow.ToString("O");
+        List<(string MessageId, string AuthorName, string Content)> remainingSegments = segments.ToList();
+        List<ChatMessage> assistantMessages = newMessages.Where(message => message.Role != ChatRole.User).ToList();
 
-        foreach (ChatMessage message in newMessages.Where(message => message.Role != ChatRole.User))
+        for (int messageIndex = 0; messageIndex < assistantMessages.Count; messageIndex++)
         {
-            (string MessageId, string AuthorName, string Content)? segment =
+            ChatMessage message = assistantMessages[messageIndex];
-                segmentIndex < segments.Count ? segments[segmentIndex] : null;
+            (string MessageId, string AuthorName, string Content)? segment = TryMatchSegment(
+                message,
+                remainingSegments,
+                assistantMessages.Count - messageIndex,
+                command.Pattern,
+                fallbackAgent);
             string content = message.Text ?? segment?.Content ?? string.Empty;
             if (string.IsNullOrWhiteSpace(content))
             {
@@ -46,7 +52,7 @@ internal static class WorkflowTranscriptProjector
 
             if (segment.HasValue)
             {
-                segmentIndex++;
+                remainingSegments.Remove(segment.Value);
             }
 
             fallbackOutputIndex++;
@@ -80,6 +86,51 @@ internal static class WorkflowTranscriptProjector
         return mapped;
     }
 
+    private static (string MessageId, string AuthorName, string Content)? TryMatchSegment(
+        ChatMessage message,
+        IReadOnlyList<(string MessageId, string AuthorName, string Content)> remainingSegments,
+        int remainingMessageCount,
+        PatternDefinitionDto pattern,
+        AgentIdentity? fallbackAgent)
+    {
+        if (remainingSegments.Count == 0)
+        {
+            return null;
+        }
+
+        string? messageText = string.IsNullOrWhiteSpace(message.Text) ? null : message.Text;
+        if (messageText is not null)
+        {
+            string resolvedAuthorName = ResolveProjectedAuthorName(
+                pattern,
+                message.AuthorName,
+                fallbackIdentifier: null,
+                fallbackAgent);
+
+            (string MessageId, string AuthorName, string Content)? authorMatchedSegment = remainingSegments.FirstOrDefault(
+                segment => string.Equals(segment.Content, messageText, StringComparison.Ordinal)
+                    && string.Equals(
+                        AgentIdentityResolver.ResolveDisplayAuthorName(pattern, segment.AuthorName),
+                        resolvedAuthorName,
+                        StringComparison.Ordinal));
+            if (authorMatchedSegment.HasValue)
+            {
+                return authorMatchedSegment.Value;
+            }
+
+            (string MessageId, string AuthorName, string Content)? contentMatchedSegment = remainingSegments.FirstOrDefault(
+                segment => string.Equals(segment.Content, messageText, StringComparison.Ordinal));
+            if (contentMatchedSegment.HasValue)
+            {
+                return contentMatchedSegment.Value;
+            }
+        }
+
+        return remainingSegments.Count == remainingMessageCount
+            ? remainingSegments[0]
+            : null;
+    }
+
     public static List<ChatMessage> SelectNewOutputMessages(
         IReadOnlyList<ChatMessage> outputMessages,
         IReadOnlyList<ChatMessage> inputMessages)

sidecar/tests/Eryx.AgentHost.Tests/CopilotAgentBundleTests.cs

@@ -1,90 +0,0 @@
-using Eryx.AgentHost.Contracts;
-using Eryx.AgentHost.Services;
-
-namespace Eryx.AgentHost.Tests;
-
-public sealed class CopilotAgentBundleTests
-{
-    [Fact]
-    public void ShouldDisableSessionTools_DisablesScratchpadAgents()
-    {
-        PatternDefinitionDto pattern = CreatePattern(
-            mode: "sequential",
-            CreateAgent("agent-primary", "Primary"));
-
-        bool disabled = CopilotAgentBundle.ShouldDisableSessionTools(
-            pattern,
-            pattern.Agents[0],
-            workspaceKind: "scratchpad");
-
-        Assert.True(disabled);
-    }
-
-    [Fact]
-    public void ShouldDisableSessionTools_DisablesOnlyHandoffEntryAgent()
-    {
-        PatternDefinitionDto pattern = CreatePattern(
-            mode: "handoff",
-            CreateAgent("agent-handoff-triage", "Triage"),
-            CreateAgent("agent-handoff-runtime", "Runtime Specialist"));
-
-        bool triageDisabled = CopilotAgentBundle.ShouldDisableSessionTools(
-            pattern,
-            pattern.Agents[0],
-            workspaceKind: "project");
-        bool specialistDisabled = CopilotAgentBundle.ShouldDisableSessionTools(
-            pattern,
-            pattern.Agents[1],
-            workspaceKind: "project");
-
-        Assert.True(triageDisabled);
-        Assert.False(specialistDisabled);
-    }
-
-    [Fact]
-    public void ShouldDisableSessionTools_LeavesNonHandoffProjectAgentsEnabled()
-    {
-        PatternDefinitionDto pattern = CreatePattern(
-            mode: "sequential",
-            CreateAgent("agent-analyst", "Analyst"),
-            CreateAgent("agent-builder", "Builder"));
-
-        bool disabled = CopilotAgentBundle.ShouldDisableSessionTools(
-            pattern,
-            pattern.Agents[0],
-            workspaceKind: "project");
-
-        Assert.False(disabled);
-    }
-
-    private static PatternDefinitionDto CreatePattern(string mode, params PatternAgentDefinitionDto[] agents)
-    {
-        return new PatternDefinitionDto
-        {
-            Id = $"pattern-{mode}",
-            Name = mode,
-            Mode = mode,
-            Availability = "available",
-            Agents = agents,
-            Graph = PatternGraphResolver.CreateDefault(new PatternDefinitionDto
-            {
-                Id = $"pattern-{mode}",
-                Name = mode,
-                Mode = mode,
-                Availability = "available",
-                Agents = agents,
-            }),
-        };
-    }
-
-    private static PatternAgentDefinitionDto CreateAgent(string id, string name)
-    {
-        return new PatternAgentDefinitionDto
-        {
-            Id = id,
-            Name = name,
-            Instructions = $"You are {name}.",
-            Model = "gpt-5.4",
-        };
-    }
-}

sidecar/tests/Eryx.AgentHost.Tests/CopilotWorkflowRunnerTests.cs

@@ -330,6 +330,47 @@ public sealed class CopilotWorkflowRunnerTests
         Assert.Equal("The button is in place.", message.Content);
     }
 
+    [Fact]
+    public void ProjectCompletedMessages_PrefersContentMatchedStreamingSegmentOverPosition()
+    {
+        RunTurnCommandDto command = new()
+        {
+            RequestId = "turn-1",
+            SessionId = "session-1",
+            Pattern = new PatternDefinitionDto
+            {
+                Id = "pattern-handoff",
+                Name = "Handoff Support Flow",
+                Mode = "handoff",
+                Availability = "available",
+                Agents =
+                [
+                    CreateAgent(id: "agent-handoff-triage", name: "Triage"),
+                    CreateAgent(id: "agent-handoff-runtime", name: "Runtime Specialist"),
+                ],
+            },
+        };
+
+        IReadOnlyList<ChatMessageDto> messages = WorkflowTranscriptProjector.ProjectCompletedMessages(
+            command,
+            [
+                new ChatMessage(ChatRole.Assistant, "Done — GoogleClient.cs now contains the requested class.")
+                {
+                    AuthorName = "assistant",
+                },
+            ],
+            [
+                ("msg-1", "Triage", "I'll hand this to a coding specialist."),
+                ("msg-2", "Runtime Specialist", "Done — GoogleClient.cs now contains the requested class."),
+            ],
+            new AgentIdentity("agent-handoff-runtime", "Runtime Specialist"));
+
+        ChatMessageDto message = Assert.Single(messages);
+        Assert.Equal("msg-2", message.Id);
+        Assert.Equal("Runtime Specialist", message.AuthorName);
+        Assert.Equal("Done — GoogleClient.cs now contains the requested class.", message.Content);
+    }
+
     [Fact]
     public void ProjectCompletedMessages_DropsBlankAssistantOutputMessages()
     {