Best Open-Source Agent Harnesses for Local LLMs in 2026
A 2026 guide ranks 11 open-source agent harnesses, including OpenCode, Goose, Cline, and OpenHands, by local-LLM support, licensing, and safety controls.
The guide ranks 11 open-source LLM agent harnesses by OSI license, documented local runtimes, maintenance status, and safety controls, using GitHub data read September 18, 2026. OpenCode documents Ollama, LM Studio, and llama.cpp setups across 75+ providers; Pi offers a minimal four-tool harness and was acquired by Earendil in April 2026; Goose is Rust-based with 70+ MCP extensions under the Linux Foundation's Agentic AI Foundation. Cline defaults to per-action approvals, while OpenHands recommends Qwen3.6-35B-A3B with at least 24GB VRAM and 32,768-token context.
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