From 2392255f9f3c173a0a17a69cbbf9fc836f767a83 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Thu, 14 May 2026 12:58:35 +0000
Subject: [PATCH] Add comment explaining unusual Throw.IfNull use for null
 elements inside collection

Agent-Logs-Url: https://github.com/microsoft/agent-framework/sessions/c5655707-5b0b-44f3-98a9-5f3961e32cfe

Co-authored-by: lokitoth <6936551+lokitoth@users.noreply.github.com>
---
 dotnet/src/Microsoft.Agents.AI.Workflows/SwitchBuilder.cs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/dotnet/src/Microsoft.Agents.AI.Workflows/SwitchBuilder.cs b/dotnet/src/Microsoft.Agents.AI.Workflows/SwitchBuilder.cs
index bee9947a6b..66ac3e6908 100644
--- a/dotnet/src/Microsoft.Agents.AI.Workflows/SwitchBuilder.cs
+++ b/dotnet/src/Microsoft.Agents.AI.Workflows/SwitchBuilder.cs
@@ -40,6 +40,7 @@ public sealed class SwitchBuilder
 
         foreach (ExecutorBinding executor in executors)
         {
+            // Explicit name: null element inside the collection argument.
             Throw.IfNull(executor, $"{nameof(executors)}[{executorIndex++}]");
 
             if (!this._executorIndicies.TryGetValue(executor.Id, out int index))
@@ -71,6 +72,7 @@ public sealed class SwitchBuilder
 
         foreach (ExecutorBinding executor in executors)
         {
+            // Explicit name: null element inside the collection argument.
             Throw.IfNull(executor, $"{nameof(executors)}[{executorIndex++}]");
 
             if (!this._executorIndicies.TryGetValue(executor.Id, out int index))