Just like J-Man said, rsbotting got best slayer bot.
Slayer Bot take a little bit more time to set up unlike other bots. The Slayer Bot does all the walking, talking and equiping required slayer equipment for you for specific slayer monster.
But what you must set up yourself is to set up specific armor you want the bot to equip for specific task.
For example, let say your task is Aberrant spectre, everybody knows that this monster attack with Magic, and does a fair amount of damage. The bot will talk to the slayer master, accept the task, equip a Nose Peg or SLayer Helmet and walk to Aberrant Spectre for you. But you have to set up the bot so that everytime you get a task for Aberrant SPectre, it equips a desired armor and weapon to fight Aberrant Spectre, which should be a high mage defence armor.
If you do not set up the bot to make it equip a desired armor and weapon every time it gets Aberrant spectre as a task, it will just use the armor and weapon it had before.
Get it?
Once you have your armor and weapons assigned for specific slayer monster that it needs to be, then your pretty much set. The bot can run all day and night if you do everything perfect. Right now, i have finished setting up my bot and it is now able to run all day and night.