The fundamental flaw with asking an LLM to "fix this layout" is that the LLM has never seen the layout. It only sees the instructions for building it. Trace bridges this gap by acting as a sensory organ for your AI. Through the Trace MCP server, an agent can request a structural DOM snapshot, computed styles, or even a visual diff. This paradigm shift allows for entirely new workflows: "Fix the overlap on the mobile nav" becomes a soluble problem because the agent can actually query the element sizes and viewport dimensions.