StepFun Step 5 Preview: sparse MoE for agent workloads

StepFun Step 5 Preview: sparse MoE for agent workloads

StepFun Step 5 Preview is circulating as a sparse Mixture-of-Experts shape aimed at agent workloads: roughly ~600B total / ~27B active, 1M context, text+vision — figures framed as vendor/X-shaped claims, not independently audited here. Open weights are claimed for 2026-10-15 (labeled claimed until a primary release note lands).

Secondary cite: X trending summary · 2026-09-20.

FLAG — unverified $: Circulating cost chatter (e.g. “~1/8 Claude Opus” task cost) is an X/secondary rumor, not a fact in this draft. Do not treat $/token or ratio claims as verified until a primary price card or vendor note exists. No invented dollars.

Speculation (labeled): if open weights land on the claimed 2026-10-15 date, agent routing tables get another sparse option — still calendar speculation, not a release guarantee.Osprey Desk speculation — not StepFun primary

Soft land (optional): Lodestar as an EU control-plane posture for routing agent models (open vs closed) — mix discussion only; no invented latency or $.

Draft only — do not publish without editorial review.