Show HN: Zkit – Go libraries for building agents, not a framework

Zkit, a set of Go libraries for building AI agents, has been released as open-source software. The libraries provide modular components including a streaming runner, tool dispatch, guardrails, compaction, and provider adapters for multiple AI models. The project aims to offer a lightweight alternative to agent frameworks by allowing developers to compose only the pieces they need.

zkit zkit Go packages for building agents: a streaming loop, tool dispatch, guardrails, compaction, and provider adapters. go get github.com/zarldev/zarlmono/zkit Import what you need. Compose the rest. What is zkit? Section titled “What is zkit?” what-is-zkit zkit is a set of small Go packages for building agents. Take the pieces you need and ignore the rest. Each package has a narrow interface and no framework ceremony. The runner is the streaming, tool-calling agent loop. Around it are tools, guardrails, compaction, providers, verified completion, and the foundation packages underneath. Core packages zkit/agent /zarlmono/runner/ Runner Streaming loop with tool calls, steering, compaction hooks, and per-call timeouts. zkit/ai /zarlmono/tools/ Tools Registry, two-method Tool interface, reflection schemas, JSON repair, MCP. zkit/agent /zarlmono/guardrails/ Guardrails Middleware around tool dispatch: schema repair, shell policy, repetition detection, verifier feedback. zkit/agent /zarlmono/compaction/ Compaction History-shrinking strategies behind one interface, with budget-driven triggers. zkit/ai /zarlmono/providers/ Providers OpenAI, Anthropic, Gemini, DeepSeek, llama.cpp, Ollama, and OAuth backends behind one contract. zkit/agent /zarlmono/pursue/ Verified completion Re-drive attempts against real-world state — tests passing, files present — not the transcript. Built with zkit These products share the same repo and the same packages. TUI agent /zarlmono/zarlcode/ zarlcode A terminal coding agent: runner, guardrails, sandboxed shell, sub-agents, SQLite sessions. Local assistant /zarlmono/zarlai/ zarlai A local multimodal assistant: speech, vision, home automation, autonomous tasks. Evaluation /zarlmono/swebench-eval/ swebench-eval A SWE-bench driver built from the same packages as the TUI. Where to go next Section titled “Where to go next” where-to-go-next — install zkit and run your first agent. Getting started — see how the packages layer. Architecture — understand the loop. Runner