Vercel Sandbox creation now returns a ready sandbox

Vercel has updated Sandbox.create() so that it resolves only after snapshot restoration completes. This ensures the returned sandbox is immediately ready to run commands and read or write files, removing the previous wait time for the first operation.

Impact on Latency and Errors

The time required for snapshot restoration now counts toward the creation phase rather than the first user operation. Consequently, creation latency increases by approximately 50 ms at the p50 percentile, with potentially larger increases for uncached snapshots. However, the total time elapsed through the first operation remains unchanged.

Additionally, startup errors now cause Sandbox.create() to reject immediately, rather than surfacing during subsequent operations. This change applies automatically to all users, requiring no SDK upgrades or configuration changes.