Grist is an open-source coding harness that uses the Opencode v2 framework, leveraging the jev model for task routing and integrating with cheaper models like deepseek and Opus 5.5. It also incorporates the Sol-Pi methodology for cost-cutting and loads engineering standards through Doctrine injection. The tool has a real control plane for escalation, permission, and verification hooks, and can be run with a key from Openrouter or Vercel AI gateway. It also supports connecting to Meta Muse for coding tasks.