Rivet is an impressive open-source visual AI workflow builder developed by Ironclad that makes designing complex AI agent pipelines remarkably intuitive. Its node-based graph editor allows developers to visually construct, debug, and iterate on LLM-powered workflows without getting lost in spaghetti code. The tool excels at chaining prompts, managing context, and orchestrating multi-step AI interactions with clear visual feedback at each stage. Being completely free and open-source is a major advantage, lowering the barrier to entry and fostering community contributions. The TypeScript SDK and API support make integration into existing applications straightforward. Strengths include excellent debugging capabilities, real-time execution visualization, and support for multiple LLM providers. The visual approach dramatically reduces the complexity of building sophisticated AI chains. Limitations include a steeper learning curve for non-developers compared to some no-code alternatives, and the ecosystem of pre-built components is still growing compared to more established platforms. Overall, Rivet is one of the best open-source options for teams building production-grade AI workflows who want full control over their stack.