Code:
register_concmd("amx_kick", "cmdKick", ADMIN_KICK, "<name or #userid> [reason]")
register_concmd("amx_ban", "cmdBan", ADMIN_BAN, "<name or #userid> <minutes> [reason]")
register_concmd("amx_banip", "cmdBanIP", ADMIN_BAN, "<name or #userid> <minutes> [reason]")
register_concmd("amx_addban", "cmdAddBan", ADMIN_BAN, "<authid or ip> <minutes> [reason]")
register_concmd("amx_unban", "cmdUnban", ADMIN_BAN, "<authid or ip>")
register_concmd("amx_slay", "cmdSlay", ADMIN_SLAY, "<name or #userid>")
register_concmd("amx_slap", "cmdSlap", ADMIN_SLAY, "<name or #userid> [power]")
register_concmd("amx_leave", "cmdLeave", ADMIN_KICK, "<tag> [tag] [tag] [tag]")
register_concmd("amx_pause", "cmdPause", ADMIN_CVAR, "- pause or unpause the game")
register_concmd("amx_who", "cmdWho", ADMIN_ADMIN, "- displays who is on server")
register_concmd("amx_cvar", "cmdCvar", ADMIN_CVAR, "<cvar> [value]")
register_concmd("amx_plugins", "cmdPlugins", ADMIN_ADMIN)
register_concmd("amx_modules", "cmdModules", ADMIN_ADMIN)
register_concmd("amx_map", "cmdMap", ADMIN_MAP, "<mapname>")
register_concmd("amx_cfg", "cmdCfg", ADMIN_CFG, "<filename>")
register_concmd("amx_nick", "cmdNick", ADMIN_SLAY, "<name or #userid> <new nick>")
register_clcmd("amx_rcon", "cmdRcon", ADMIN_RCON, "<command line>")
register_clcmd("amx_showrcon", "cmdShowRcon", ADMIN_RCON, "<command line>")
register_clcmd("pauseAck", "cmdLBack")
You're looking or admincmd.sma. Change the third parameter to what suits.
Custom flags are defined as ADMIN_LEVEL_A, ADMIN_LEVEL_B and so on.