**Show HN: Build A Harness – open-source, modular harness layer for AI agents**

> Apache 2.0 visual canvas for AI agent harnesses. Draw once, run on LangGraph, CrewAI, Mastra, or MS Agent Framework. Langfuse observability, HITL, REST/MCP/A2A. Build A Harness Harness Node library Get started How it works Frameworks Examples Contribute FAQ Harness engineering GitHub OPEN SOURCE · VISUAL CANVAS · APACHE 2.0 Design, test, and deploy AI agent harnesses. Pick the nodes your agent needs. Draw the graph....

**来源信息**
- **来源**：Hacker News：AI 热帖
- **分类**：ai-products
- **发布时间**：2026-06-24 22:11（北京时间）
- **原文**：[打开原文](https://buildaharness.com/)