Local LLMs for AI Agents: When It Makes Sense, When It Doesn't

A coding agent burns through tokens. The monthly bill from a frontier API provider for a single moderately active agent lands somewhere between fifty and a few hundred dollars, and the natural reaction is to check whether a one-time hardware purchase would be cheaper. The naive comparison — dollars per million tokens versus dollars amortized over five years — almost always concludes that local wins. The honest comparison rarely does, at least for coding workloads, at least as of mid-2026. The reason is a capability gap that doesn’t show up in any cost spreadsheet.