A hands-on guide to building a fully functional CLI AI agent with tool calling, streaming, evaluations, context management, and human-in-the-loop safety. Available in five languages — plus a vibe-coding edition for product roles.
Built with the Vercel AI SDK, Zod schemas, and React + Ink for the terminal UI. The most framework-rich approach.
Uses the OpenAI SDK, dataclasses, and Rich + Prompt Toolkit for UI. The most approachable path to understanding agents.
Raw HTTP with reqwest. Manual SSE parsing. Trait objects for tool dispatch. Ratatui for terminal UI. No SDK, full control.
Standard library net/http. Goroutines and channels for the agent loop. Bubble Tea for terminal UI. Single static binary, no framework.
java.net.http.HttpClient with Jackson. Sealed types and records. Virtual threads for concurrency. Lanterna for terminal UI.
For product managers, owners, and analysts. Build the same Python agent by guiding a coding agent through prompts — no programming required.