Perplexity says Amazon fired off a “legal threat” demanding the company stop letting users’ AI assistants roam the site.

Amazon has sued Perplexity after accusing the company of violating its terms of service with the agentic shopping capabilities of its Comet AI browser.

Amazon.com has sent a cease-and-desist letter to Perplexity that demands the artificial intelligence startup prevents its Comet browser from making purchases on Amazon.

Amazon sues Perplexity, alleging Comet made undisclosed purchases. The case puts autonomous AI on trial and could set early rules for how agents operate online.