How Upgrading to AI SDK v6 Cut My Agent's Token Usage by 57%

I built Browse Bot, an AI browser extension that acts like an agent - it can click buttons, fill forms, and navigate pages based on natural language commands. During beta-testing we have encountered some problems: it would hang mid-task, burn through tokens, and sometimes just stop without explanation. Then AI SDK v6 came out, bringing changes that allowed Browse Bot to make a significant leap in effiency. Let me explain. The Problem: Death by a Thousand LLM Calls Our internal test suite runs real tasks through the agent: "add items from favorites to cart," "fill out this form," "log in to the site." Each test launches Firefox with the extension installed, gives the agent a text prompt, and checks if it succeeded (Did the DOM update? Did localStorage change? Did it call the right tool?). Before the upgrade, the pass rate was unstable: some tasks worked, but others hung. The agent would click the wrong element, or worse, click nothing at all while the LLM kept thinking. When we dug into