PowerShell Exec MCP Server

Instructions

Input Schema

Input Schema (JSON Schema)

Implementation Reference

• server.py:587-658 (handler)

  The primary handler function for the MCP tool 'generate_bigfix_relevance_script'. It constructs template parameters from inputs and delegates to generate_script_from_template to produce the final BigFix relevance script using the 'bigfix_relevance' template.
  async def generate_bigfix_relevance_script( description: str, relevance_logic: str, output_path: Optional[str] = None, timeout: Optional[int] = 60 ) -> str: """Generate a BigFix relevance script to determine if computers need action. Creates a PowerShell relevance script that follows IBM BigFix best practices: - Proper output format (TRUE/FALSE for BigFix consumption) - BigFix client log integration for monitoring - Event log integration for troubleshooting - Comprehensive error handling and logging - Fast execution optimized for frequent evaluations 💡 TIP: For complete BigFix deployments, you need BOTH relevance and action scripts. Consider using 'generate_bigfix_script_pair' to create both scripts together with matching logic. IBM BigFix References: - Relevance Language Guide: https://help.hcltechsw.com/bigfix/11.0/relevance/Relevance/c_relevance_language.html - Action Scripts: https://help.hcltechsw.com/bigfix/11.0/platform/Platform/Console/c_creating_action_scripts.html - Best Practices: https://help.hcltechsw.com/bigfix/11.0/platform/Platform/Console/c_best_practices_for_creating_fixlets.html - Client Logging: https://help.hcltechsw.com/bigfix/11.0/platform/Platform/Installation/c_bes_client_logging.html Args: description: Clear description of what the script should check (e.g., 'Check if Chrome needs updating', 'Verify Windows patches are current') relevance_logic: PowerShell code that determines relevance. Use 'Complete-Relevance -Relevant $true/$false -Message "status"' to indicate result output_path: Optional file path where the script will be saved. If not provided, returns script content timeout: Command timeout in seconds (1-300, default 60) Returns: Generated script content or path where script was saved Example: Generate a script to check if Chrome needs updating: ``` result = await generate_bigfix_relevance_script( description="Check if Chrome browser needs updating to version 100.0.0.0 or higher", relevance_logic=''', try { $app = Get-ItemProperty "HKLM:\\Software\\Microsoft\\Windows\\CurrentVersion\\App Paths\\chrome.exe" -ErrorAction Stop $version = (Get-Item $app.'(Default)').VersionInfo.FileVersion $needsUpdate = [version]$version -lt [version]"100.0.0.0" Complete-Relevance -Relevant $needsUpdate -Message "Chrome version: $version (Target: 100.0.0.0+)" } catch { Complete-Relevance -Relevant $true -Message "Chrome not found or inaccessible - installation needed" } ''', output_path="chrome_relevance.ps1" ) ``` Tips: - Keep relevance logic fast and efficient (evaluated frequently) - Return TRUE when action is needed, FALSE when compliant - Always use Complete-Relevance function for proper BigFix output format - Use try-catch blocks for robust error handling - Test relevance logic thoroughly across different environments - Use Write-BigFixLog for detailed progress tracking """ params = { "SYNOPSIS": f"BigFix Relevance Script - {description}", "DESCRIPTION": description, "DATE": datetime.now().strftime('%Y-%m-%d'), "RELEVANCE_LOGIC": relevance_logic } if output_path: output_path = ensure_directory(output_path) return await generate_script_from_template("bigfix_relevance", params, output_path, timeout)
• server.py:159-196 (helper)

  Shared utility function that loads a PowerShell template file, substitutes parameters, and returns or saves the generated script. Critical helper used by generate_bigfix_relevance_script and other generation tools.
  async def generate_script_from_template( template_name: str, parameters: Dict[str, Any], output_path: Optional[str] = None, timeout: Optional[int] = 60 ) -> str: """Generate a PowerShell script from a template. Args: template_name: Name of the template to use (without .ps1 extension) parameters: Dictionary of parameters to replace in the template output_path: Where to save the generated script (optional) timeout: Command timeout in seconds (1-300, default 60) Returns: Generated script content or path where script was saved """ template_path = os.path.join(TEMPLATES_DIR, f"{template_name}.ps1") if not os.path.exists(template_path): raise ValueError(f"Template {template_name} not found") with open(template_path, 'r') as f: template_content = f.read() # Replace template variables script_content = template_content parameters['DATE'] = datetime.now().strftime('%Y-%m-%d') for key, value in parameters.items(): script_content = script_content.replace(f"{{{{{key}}}}}", str(value)) if output_path: with open(output_path, 'w') as f: f.write(script_content) return f"Script generated and saved to: {output_path}" return script_content
• server.py:306-325 (helper)

  Utility functions normalize_path and ensure_directory used by script generation tools to handle output paths safely, called from generate_bigfix_relevance_script.
  def normalize_path(path: str) -> str: """Convert relative paths to absolute using current working directory.""" if not path: raise ValueError("Path cannot be empty") if path.startswith(('./','.\\')): path = path[2:] if not os.path.isabs(path): path = os.path.join(os.getcwd(), path) return os.path.abspath(path) @mcp.tool() def ensure_directory(path: str) -> str: """Ensure directory exists and return absolute path.""" abs_path = normalize_path(path) if os.path.splitext(abs_path)[1]: # If path has an extension dir_path = os.path.dirname(abs_path) else: dir_path = abs_path os.makedirs(dir_path, exist_ok=True) return abs_path
• server.py:26-36 (registration)

  MCP server initialization with FastMCP. All @mcp.tool() decorators register tools like generate_bigfix_relevance_script automatically with this server instance.
  mcp = FastMCP( "PowerShell Integration Server", description="Secure PowerShell command execution and script generation for Windows system administration, including Intune and BigFix deployment scripts", dependencies=["asyncio", "psutil>=5.9.0"], capabilities={ "tools": True, "resources": True, "resourceTemplates": True, "prompts": True } )