Fix the response from MCP server.

Public/Invoke-HandleRequest.ps1

@@ -44,8 +44,69 @@ function Invoke-HandleRequest {
         $toolName = $request.params.name
         $targetArgs = $request.params.arguments | ConvertTo-Json -Depth 10 | ConvertFrom-Json -Depth 10 -AsHashtable
 
+        # Derive the set of allowed tool names from the configured tools list JSON.
+        $allowedToolNames = @()
+        try {
+            $parsedTools = $toolsListJson | ConvertFrom-Json -Depth 10
+
+            if ($parsedTools -is [System.Array]) {
+                # Expecting an array of tool objects with a 'name' property.
+                $allowedToolNames = $parsedTools | ForEach-Object { $_.name } | Where-Object { $_ }
+            }
+            elseif ($parsedTools -ne $null) {
+                # Handle object shapes like @{ tools = @(@{ name = "..." }, ...) } or a single tool object.
+                if ($parsedTools.PSObject.Properties.Name -contains 'tools' -and $parsedTools.tools) {
+                    $allowedToolNames = $parsedTools.tools | ForEach-Object { $_.name } | Where-Object { $_ }
+                }
+                elseif ($parsedTools.PSObject.Properties.Name -contains 'name') {
+                    $allowedToolNames = @($parsedTools.name) | Where-Object { $_ }
+                }
+            }
+        }
+        catch {
+            # If parsing fails, leave $allowedToolNames empty to avoid executing arbitrary tools.
+            $allowedToolNames = @()
+        }
+
+        # Validate that the requested tool name is in the allowed list.
+        if (-not ($allowedToolNames -and ($allowedToolNames -contains $toolName))) {
+            $errorResponse = [ordered]@{
+                jsonrpc = "2.0"
+                id      = $request.id
+                error   = @{
+                    code    = -32602
+                    message = "Invalid or unauthorized tool name: '$toolName'."
+                }
+            }
+
+            return ($errorResponse | ConvertTo-Json -Depth 10 -Compress)
+        }
         $result = & $toolName @targetArgs
 
+        $resultText = if ($null -eq $result) {
+            ""
+        }
+        elseif ($result -is [string]) {
+            $result
+        }
+        elseif ($result -is [ValueType]) {
+            $result.ToString()
+        }
+        else {
+            try {
+                $result | ConvertTo-Json -Depth 100
+            }
+            catch {
+                # Fallback to a safer string representation if JSON serialization fails
+                try {
+                    $result | Out-String
+                }
+                catch {
+                    $result.ToString()
+                }
+            }
+        }
+
         # Log structured data
         Write-Log -LogEntry @{
             RequestId = $request.id
@@ -63,7 +124,7 @@ function Invoke-HandleRequest {
                 content = @(
                     [ordered]@{
                         type = "text"
-                        text = $result | Out-String
+                        text = $resultText
                     }
                 )
                 isError = $false