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Changelog

GELO Hosted Optimizer Launch Promo

Hosted GELO is available for checkpoint-native long-horizon optimization, with a launch promo for hosted proposer spend.

Thursday, June 11, 20261 min read
gelohosted-optimizersprompt-optimizationpromo

TL;DR

  • GELO is now available as a hosted optimizer for long-horizon agent tasks.
  • The first 20 organizations can claim $500 of hosted Go-Ex proposer spend.
  • Promo grants are valid for 14 days after claim.
  • Task-container policy LLM calls remain owned by the task container and its provider credentials.

What shipped

GELO, the Go-Explore Long-Horizon Optimizer, runs checkpoint-native prompt search against task containers. It records frontier states, opens theme searches from those checkpoints, and promotes candidates only when heldout replay supports the change.

Hosted submits use the synth-optimizers SDK and CLI. Synth automatically claims the GELO launch promo for hosted go-ex submits when first-20 slots remain, checks for at least $1 of hosted proposer-spend headroom before queueing, and caps each organization at one queued or running hosted GELO job while using the promo.

Who this affects

  • Teams building long-horizon task containers with checkpoint and resume support.
  • SDK and CLI users submitting hosted GELO runs through Synth.
  • Readers of the GELO launch post who want to run the optimizer on their own task.

Learn more

  • GELO research report
  • Hosted GELO quickstart and launch promo terms
  • GELO skill
  • Crafter + GELO cookbook
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