diff --git a/eng/scripts/Analyze-Code.ps1 b/eng/scripts/Analyze-Code.ps1
index 087f1a6984..bb2e188935 100644
--- a/eng/scripts/Analyze-Code.ps1
+++ b/eng/scripts/Analyze-Code.ps1
@@ -84,6 +84,17 @@ try {
         Write-Host "✅ Tool id validation passed."
     }
 
+    # Run namespace validation
+    $namespaceResult = & "$PSScriptRoot/Test-Namespace.ps1"
+
+    if ($LASTEXITCODE -ne 0) {
+        Write-Host "❌ Namespace validation failed"
+        Write-Host "$($namespaceResult.ViolationCount) file(s) missing namespace declarations. Review the above output for details."
+        $hasErrors = $true
+    } else {
+        Write-Host "✅ Namespace validation passed."
+    }
+
     if($hasErrors) {
         exit 1
     }
diff --git a/eng/scripts/Test-Namespace.ps1 b/eng/scripts/Test-Namespace.ps1
new file mode 100644
index 0000000000..4d7e55fbd0
--- /dev/null
+++ b/eng/scripts/Test-Namespace.ps1
@@ -0,0 +1,90 @@
+#!/usr/bin/env pwsh
+#Requires -Version 7
+
+<#
+.SYNOPSIS
+    Validates that all C# class files have a namespace declaration.
+
+.DESCRIPTION
+    Scans all .cs files under core/, servers/, and tools/ directories (excluding
+    obj/, bin/, and auto-generated files) and ensures each file contains a
+    namespace declaration. Files without a namespace cause compilation issues
+    and pollute the global namespace.
+
+.PARAMETER Path
+    Root directory to scan. Defaults to the repository root.
+
+.OUTPUTS
+    Returns an object with ViolationCount property. Sets exit code 1 if violations found.
+#>
+
+param(
+    [string]$Path
+)
+
+$ErrorActionPreference = 'Stop'
+
+. "$PSScriptRoot/../common/scripts/common.ps1"
+
+if (-not $Path) {
+    $Path = $RepoRoot
+}
+
+$rootPath = (Resolve-Path $Path).Path.TrimEnd('\', '/')
+
+$searchDirs = @(
+    Join-Path $rootPath "core"
+    Join-Path $rootPath "servers"
+    Join-Path $rootPath "tools"
+)
+
+$violations = @()
+
+foreach ($dir in $searchDirs) {
+    if (-not (Test-Path $dir)) {
+        continue
+    }
+
+    $csFiles = Get-ChildItem -Path $dir -Filter "*.cs" -Recurse | Where-Object {
+        $_.FullName -notmatch '[/\\](obj|bin)[/\\]' -and
+        $_.FullName -notmatch '\.g\.cs$' -and
+        $_.FullName -notmatch '\.generated\.cs$' -and
+        $_.FullName -notmatch 'GlobalUsings\.cs$' -and
+        $_.FullName -notmatch 'AssemblyInfo\.cs$' -and
+        $_.FullName -notmatch 'AssemblyAttributes\.cs$' -and
+        $_.Name -ne 'Program.cs' -and
+        $_.Name -ne 'Usings.cs' -and
+        $_.FullName -notmatch '[/\\]templates[/\\]'
+    }
+
+    foreach ($file in $csFiles) {
+        $content = Get-Content $file.FullName -Raw
+
+        if ([string]::IsNullOrWhiteSpace($content)) {
+            continue
+        }
+
+        if ($content -notmatch '(?m)^\s*namespace\s+[A-Za-z_][A-Za-z0-9_.]*\s*;') {
+            $relativePath = [System.IO.Path]::GetRelativePath($rootPath, $file.FullName)
+            $violations += $relativePath
+        }
+    }
+}
+
+if ($violations.Count -gt 0) {
+    Write-Host "❌ Found $($violations.Count) C# file(s) missing a namespace declaration:"
+    Write-Host ""
+    foreach ($v in $violations) {
+        Write-Host "  - $v"
+    }
+    Write-Host ""
+    Write-Host "All C# class files must declare a namespace. Use file-scoped namespaces:"
+    Write-Host "  namespace Azure.Mcp.Tools.MyToolset.Commands;"
+    Write-Host ""
+
+    $result = [PSCustomObject]@{ ViolationCount = $violations.Count }
+    Write-Output $result
+    exit 1
+} else {
+    Write-Output ([PSCustomObject]@{ ViolationCount = 0 })
+}
diff --git a/tools/Azure.Mcp.Tools.Speech/src/Commands/SpeechJsonContext.cs b/tools/Azure.Mcp.Tools.Speech/src/Commands/SpeechJsonContext.cs
index 7af05dc6e7..68a45a4874 100644
--- a/tools/Azure.Mcp.Tools.Speech/src/Commands/SpeechJsonContext.cs
+++ b/tools/Azure.Mcp.Tools.Speech/src/Commands/SpeechJsonContext.cs
@@ -8,6 +8,8 @@
 using Azure.Mcp.Tools.Speech.Models.FastTranscription;
 using Azure.Mcp.Tools.Speech.Models.Realtime;
 
+namespace Azure.Mcp.Tools.Speech.Commands;
+
 [JsonSerializable(typeof(RealtimeRecognitionContinuousResult))]
 [JsonSerializable(typeof(RealtimeRecognitionDetailedResult))]
 [JsonSerializable(typeof(RealtimeRecognitionNBestResult))]
diff --git a/tools/Fabric.Mcp.Tools.OneLake/src/Commands/File/BlobGetCommand.cs b/tools/Fabric.Mcp.Tools.OneLake/src/Commands/File/BlobGetCommand.cs
index 1d0a333cfe..994eee7381 100644
--- a/tools/Fabric.Mcp.Tools.OneLake/src/Commands/File/BlobGetCommand.cs
+++ b/tools/Fabric.Mcp.Tools.OneLake/src/Commands/File/BlobGetCommand.cs
@@ -14,6 +14,8 @@
 using Microsoft.Mcp.Core.Models.Option;
 using Microsoft.Mcp.Core.Options;
 
+namespace Fabric.Mcp.Tools.OneLake.Commands.File;
+
 [CommandMetadata(
     Id = "75d6cb4c-4e81-4e69-a4ec-eca53a7dacd9",
     Name = "download_file",