How to build an agent harness from scratch: LLM module, tools module, and the ReAct route
ryunuck · x · 2026-09-15
Elvis Saravia shares a short guide on building an agent harness from scratch: pick TypeScript or Python, feed the ReAct paper to your agent to produce a minimal implementation you can inspect, and target three parts — an LLM inference module (ideally multi-model via something like OpenRouter, with separable system prompt for context engineering), a tools module, and orchestration. Hands-on building is the best way to actually learn harnesses.
Related event: Build your own agent harness from scratch: a minimal three-module guide(3 posts)→
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