The murky, highly complex business of helping advertisers buy space on digital media is currently dominated by Google, Amazon and a handful of much smaller ad tech firms. But an array of other companies, including Salesforce, Microsoft and a new initiative led by AppNexus founder Brian O’Kelley, hopes to use new artificial intelligence tools to grab a piece of the market.

All these challengers are pitching advertisers or publishers or both on using artificial intelligence agent technology to plan ad campaigns and assess their performance once they’re underway. Core to their pitch is that AI agents—AI services designed to take action on a user’s behalf—could make it easier for marketers to compare the effectiveness of advertising on different media by analyzing their vast stores of data about past ad campaigns. But the incumbents in the category, including Amazon and Google, also plan to take advantage of agents in their ad businesses.