I Caught an LLM at the Edge of Its World

I asked a fresh Claude Opus chat what an elastic automator is. It guessed from the two words; the term wasn't in its training. Then I told it in one sentence, and the same model could refuse to collapse the term into AI agent, RPA bot, or framework. That seed observation grew a name, a metric, and a pre-registered multi-model test. The substrate is real, and the substrate is writable. For an LLM, the transient context IS the cognitive substrate.