Class BetaFallbackBlockParam

  • All Implemented Interfaces:

    
    public final class BetaFallbackBlockParam
    
                        

    A fallback block echoed back from a prior response.

    Accepted in messages[].content and never rendered into the prompt, not validated against the request's fallbacks chain or top-level model, and stripped before the sticky-routing cache key is computed.

    Callers should echo the assistant turn verbatim — block included. The block's position is load-bearing for thinking verification: the thinking runs on either side of a fallback hop carry independently-rooted verification hash chains, and this block is the only record of where one chain ends and the next begins. When thinking runs flank the boundary, omitting the block merges the runs into one contiguous span whose hashes cannot verify (the request is rejected), and moving it into the middle of a single run splits that run's chain and is likewise rejected; between non-thinking blocks the block's placement has no verification effect.