Grist

Grist is an open-source coding harness built on Opencode v2 that intelligently routes coding tasks across different AI models based on difficulty levels. It uses a four-tier system (easy, medium, hard, frontier) to match tasks with appropriate models—directing simpler work to cost-effective options like DeepSeek and complex tasks to advanced models like Claude Opus 5.5.

The harness implements the Sol-Pi methodology to further optimize costs through action fusion and observation packing techniques. It uses dependency injection for flexible configuration and aims to reduce token usage across all complexity tiers.