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nac
Give AI agents ambitious work without losing the plot. nac is an open-source harness for long-running tasks, using a central orchestrator, threads, and structured episodes to…
Install
git clone https://github.com/arcee-ai/nacInstall command taken from the project's README or registry entry. Always review code before running it.
README excerpt
Read full README on GitHub →Arcee • Documentation • Releases • Arcee Open Model API
nac is an open-source agent harness for longer, ambitious tasks — experiments, training runs, infrastructure, and prototyping that has to stay aligned with the original intent. It uses a thread-and-episode architecture inspired by slate: a central orchestrator plans and decomposes work but cannot execute commands or edit files; it only launches threads, which return episodes — structured summaries of what they accomplished. Also takes inspiration from nanocode and pi. For the technical write-up, see the nac blog post.
Quickstart
By Hand. Install the latest stable release:
curl -fsSL https://raw.githubusercontent.com/arcee-ai/nac/main/scripts/install.sh | sh
The installer puts nac-web in $HOME/.local/bin. Add that directory to your PATH if needed, then start the dashboard from your project,
nac-web
and navigate to the interface in your browser (default: http://127.0.0.1:3210).
By Agent. Nac provides a portable onboarding skill and MCP integration; paste this into your chosen agent harness to install nac, configure it, and connect the MCP:
Install the nac onboarding skill with
curl -fsSL https://raw.githubusercontent.com/arcee-ai/nac/main/scripts/install-skill.sh | sh -s -- --target agents, loadnac-onboarding, and walk me through installing nac, selecting Arcee login, ChatGPT Codex login, or an OpenAI-compatible API key, adding MCP servers, and connecting your MCP client to nac.
Upgrade. Nac ships with a native upgrade function which can be used to install the latest stable release of nac.
nac-web upgrade
Model Provider Authentication
Pick one before you start a session, or configure it later from the dashboard.
# Recommended: Arcee device-code login → Latest Open & Arcee Trinity models
nac-web arcee-auth login
# ChatGPT account via OAuth → OpenAI models
nac-web codex-auth login
# Any catalog provider (DeepSeek, Fireworks, Together, OpenAI, Anthropic, arcee-api, …)
export OPENAI_API_KEY=... # or ANTHROPIC_API_KEY, TOGETHER_API_KEY, ARCEE_API_KEY, …
More details can be found in Providers and logins and Model configuration.
Uninstall
curl -fsSL https://raw.githubusercontent.com/arcee-ai/nac/main/scripts/uninstall.sh | sh
Documentation
Contributing
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