Respan’s Span-01 and Span-01 Lite are live on OpenRouter

OpenRouter has made Respan’s Span-01 and Span-01 Lite available. A caller sends an agent span and the behaviors to check, and the models return the probability that each behavior is present. OpenRouter’s examples include whether the user is frustrated and whether a tool call is safe to run.

Respan describes Span-01 as a hyper-parallel reasoning classifier built for unseen challenges (RLAIF). Respan says it is 2x cheaper and 18% better than Jev, and 700x cheaper and 4% better than GPT-6 Luna, and that it ranks first on the Behavior Benchmark. Respan also says Span-01 Lite is better than Jev and completely free.