Because Microsoft does not like to provide this on their webpage, here are the command line instructions:
Microsoft (R) Code Metrics Command-Line Tool, Version 10.0 Copyright (C) Microsoft Corporation. All rights reserved. Help for command-line options: /file: [Short form: /f:] Assembly file(s) to analyze. /out: [Short form: /o:] Metrics results XML output file. /directory: [Short form: /d:] Location to search for assembly dependencies. /searchgac [Short form: /gac] Search the Global Assembly Cache for missing references. /platform: [Short form: /plat:] Location of framework assemblies, such as mscorlib.dll. /reference: [Short form: /ref:] Reference assemblies required for analysis. /ignoreinvalidtargets [Short form: /iit] Silently ignore invalid target files. /ignoregeneratedcode [Short form: /igc] Do not calculate metrics for generated code. /successfile [Short form: /sf] Create .lastcodemetricsssucceeded file in output report directory if no errors occur during calculation. /quiet [Short form: /q] Silence all console output other than error reporting. /help [Short form: /?] Display this help message.