Flight recorder
Research and engineering notes on model routing — including the Router Graveyard series: post-mortems of routing projects that didn't make it, and what that says about the ones that will.
Agent frameworks promised to orchestrate tools, memory, and multi-step reasoning. Most are gone, pivoted, or absorbed. What killed the category — and what actually endured.
Model aggregators promised one key, one invoice, every model. Most are gone, pivoted, or maintenance-mode. What killed the category — and what the survivors actually sell.
LLM routing looked like an obvious business in 2023. Three years later, most of the first wave is dormant, pivoted, or rebranded. What killed them — and what actually survives.