agent brief/2026-10-21

The Harness Becomes the Headline

DeepSeek open-sources its inference engine and ships a 1M-token model, while builders converge on the same verdict: agents break on plumbing, not models.

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  • Infra Ships, Parts Missing: DeepSeek open-sourced DeepInfer (Apache-2.0) with self-reported $38/GPU-hour economics — but no KV cache store or load balancers.
  • Context Race: DeepSeek-V4 pushes a 1M-token window; Meta's 30B Apache-2.0 Muse Glimmer targets local planning — both with caveats.
  • Harness First: Anthropic's draft S-1 drew the headlines, but the reported $80.7B loss is largely equity owed, not server burn.
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2026-10-20

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