Evening brief

Sunday, July 12

4 people · 0 companies · 7 topics

TL;DR Claude Fable 5 included access expires tonight; GPT-5.6 Sol Ultra’s claimed proof of the 50-year Cycle Double Cover Conjecture is still under math community review.

Models & research

  • model-releases Claude Fable 5 included access ends tonight at 11:59 PM PT on Pro/Max/Team/Enterprise plans — after this it’s credits-only at $10/$50 per Mtok, the highest pricing Anthropic has published for a GA model. Anthropic · coverage
  • model-releases GPT-5.6 (Luna/Terra/Sol) launched publicly July 9 after a US government safety review; Sol Ultra is OpenAI’s most capable model yet and 54% more token-efficient on coding. sama TechCrunch · Axios
  • ai-research GPT-5.6 Sol Ultra posted a claimed proof of the Cycle Double Cover Conjecture (open since 1973-79) using 64 parallel subagents in under an hour; OpenAI published the proof PDF and full prompt, but no peer review yet and the problem has had false proofs before. officechai · HN thread
  • model-releases Mistral released Leanstral 1.5 on July 2: 119B Apache 2.0 MoE for Lean 4 formal verification; saturates miniF2F, hits 87% on FATE-H, and found 5 previously unknown bugs across 57 OSS repos in testing. Mistral · The Decoder

People

  • emollick was an early GPT-5.6 Sol tester and described it as “faster but works with you in steps more” vs Fable; he also flagged that OpenAI hasn’t reported Sol’s score on GDPval, their own benchmark for hard autonomous tasks. X · metrics thread
  • natolambert co-authored TMax (arxiv 2606.23321), Ai2’s open RL recipe for terminal agents — TMax-27B hits 42.7% on Terminal-Bench 2.0; ships with full data, weights 2B-27B, and reproduction code. X · paper · substack
  • simonw shipped sqlite-utils 4.0 on July 7 with built-in schema migrations (promoted from sqlite-migrate) and savepoint-based nested transactions — consolidates a common two-library pattern used by his LLM tool and Datasette ecosystem. blog

Tools & dev

  • claude-code Claude Code Gov Desktop public beta launched (FedRAMP High, tamper-evident audit logs, spend governance); Claude Sonnet 5 is now the default model with 1M context at $2/$10/Mtok promotional pricing through Aug 31. changelog · releasebot
  • codex Codex Remote reached GA on July 9 — start or review agent work on a connected Mac/Windows host from the ChatGPT mobile app; Codex is now bundled into the ChatGPT desktop app. release notes

OSS

  • Google Labs’ stitch-skills gained +340 stars today: an Agent Skills library for the Stitch MCP server, compatible with Claude Code, Gemini CLI, and Cursor. GitHub
  • DesktopCommanderMCP is up +909 stars today (sponsored): MCP server giving Claude terminal control, file search, and diff editing. GitHub
  • awesome-llm-apps +549 today and OpenManus +226 today are also surging on the Python trending list.

Other

  • Anthropic’s Claude Corps fellowship first-cohort deadline is July 17: $85k/year, 1,000 fellows placed full-time at nonprofits for 12 months, backed by a $150M Anthropic commitment. Anthropic