{"slug": "show-hn-grist-open-source-coding-harness", "title": "Show HN: Grist, open source coding harness", "summary": "A developer released Grist, an open-source coding harness built on Opencode v2, which routes tasks across four tiers — easy, medium, hard and frontier — to cheaper models such as DeepSeek for simple work and Opus 5.5 for harder work. Grist adds Sol-Pi methodology, based on a recently published paper using action fusion and observation packing, plus Doctrine injection that loads engineering standards into every session, and a control plane with escalation, permission and verification hooks. The tool is available as a Mac app and a CLI installable via npm install -g grist-ai, and requires an OpenRouter or Vercel AI gateway key so one key can call both the jev decision model and the coding LLMs.", "body_md": "I built a coding harness on top of the new Opencode v2, it started with the the idea of using the new jev model for routing easy tasks to cheaper models such as deepseek and hard tasks to models such as Opus 5.5. In total in separated it into 4 rungs - easy, medium, hard and frontier.\n\nTwo more layers compound the savings: the Sol-Pi methodology based on the recently published paper which uses action fusion and observation packing and cuts roken usage within every tier. Doctrine injection loads your engineering standards into every session by default, so the agent writes code the way your team would.\n\nThere is also a real control plane - escalation, permission and verification hooks so the agent surfaces uncertainty instead of being confidently wrong in silence.\n\nRun it using your own key from Openrouter or Vercel AI gateway key, we need this since one key is able to call the jev decision model as well as the llms for coding.\n\nOne more thing I added was the ability to connect your Meta Muse to use this for coding tasks which has worked really well so far you can try it out by copying the promp for agent on the website.\n\nTwo ways you can use it today is the Mac app and the cli.\n\nHonest limitations are documented, happy to take any questions.\n\nRepo: [https://github.com/grist-ai/grist](https://github.com/grist-ai/grist)\nnpm CLI: npm install -g grist-ai\n\nComments URL: [https://news.ycombinator.com/item?id=49928275](https://news.ycombinator.com/item?id=49928275)\n\nPoints: 1\n\n# Comments: 0", "url": "https://wpnews.pro/news/show-hn-grist-open-source-coding-harness", "canonical_source": "https://grist.lol/", "published_at": "2026-10-01 23:37:11+00:00", "updated_at": "2026-10-01 23:45:37.288938+00:00", "lang": "en", "topics": ["ai-agents", "ai-tools", "developer-tools", "large-language-models", "ai-products"], "entities": ["Grist", "Opencode v2", "DeepSeek", "Opus 5.5", "Sol-Pi", "OpenRouter", "Vercel AI gateway", "Meta Muse"], "also_reported_by": [], "alternates": {"html": "https://wpnews.pro/news/show-hn-grist-open-source-coding-harness", "markdown": "https://wpnews.pro/news/show-hn-grist-open-source-coding-harness.md", "text": "https://wpnews.pro/news/show-hn-grist-open-source-coding-harness.txt", "jsonld": "https://wpnews.pro/news/show-hn-grist-open-source-coding-harness.jsonld"}}