Perplexity describes sandbox routing fix for stale executions after resume

Perplexity says that when a sandbox resumes on another machine it keeps its sandbox ID but starts a new execution, so a stale route can send requests to the older execution and return old data.

Perplexity says checking the sandbox ID alone does not catch this.

To address it, Perplexity describes signed per-request proof: each request carries short-lived proof of which execution may handle it and what access is allowed. Per Perplexity, the receiving worker checks that identity against its own runtime record and rejects mismatches before forwarding.