DeepSeek Harness, DeepSeek-V4-Pro, Grok Bot, GLM-5.3, Gemini 3.7 Flash, Muse Glimmer, Harness Evolution Papers, and More
In today’s issue:
DeepSeek open-sources its agent harness
DeepSeek-V4-Pro ships agent upgrades xAI launches Grok Bot teammates
Z.ai drops GLM-5.3 for coding
Gemini 3.7 Flash halves coding cost
Meta open-sources Muse Glimmer
Grok 4.6 hits frontier at half price
Zed launches Delta for agent teams
Evo-Bench measures harness evolution
Study finds 91.8% of skills defective
And all the top AI dev news, papers, and tools.
Top Stories #
DeepSeek Open-Sources Its Agent Harness
DeepSeek released DeepSeek Harness v0.1 as a developer preview, open-sourcing the codebase under MIT and opening it to anyone building agent harnesses.
Everything is a plugin: The harness is built on the Cordis meta-framework, a kernel that mounts, unmounts, and resolves dependencies for models, tools, skills, sessions, sandboxes, storage, loops, scheduling, and UI as independent plugins.Append-only session log: Everything the model sees is recorded, so sessions can be resumed, forked, searched, and replayed rather than reconstructed from chat history.Four runtime modes: Standard ships the full toolset, Code orchestrates operations through TypeScript, Minimal strips down for benchmark runs, and Creator is for building custom presets.Install path: Runs vianpx @deepseek-ai/dsh web
or from source, and the repo has already cleared 93,000 stars.
DeepSeek Launches V4-Pro
DeepSeek shipped V4-Pro-0813, a general availability release centered almost entirely on agent workloads.
Agentic benchmarks: 87.9 on Terminal Bench 2.1, 62.7 on DeepSWE, 74.1 on Toolathlon-Verified, 83.3 on CyberGym, and 31.8 on public AutomationBench, tested through DeepSeek Harness in minimal mode.Flexible reasoning effort: Low, high, and max tiers across V4-Pro and V4-Flash let you dial spend per task instead of paying reasoning cost on trivial calls.Native Responses API: Ships OpenAI Responses API support with one-click Codex setup, and model names stay unchanged so existing integrations keep working.Peak and off-peak pricing: New API rates take effect August 16, with off-peak rates 50% below peak for schedulable batch and agent workloads.