Reads code as a graph
Real ASTs — classes, methods, dependency edges — indexed so the agent asks for the function it needs instead of grepping blind through text.
Open source · AGPL-3.0 · runs in your terminal
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The most customizable open-source agentic coding harness.
Bring your own model — any open model, any host. Plug in an API key and go. Five safety-first systems keep long agent runs on the rails, so you can hand off real work without holding your breath.
$
npm install -g nyxthos
click to copy
Five systems, one harness
Built for long runs that don't fall apart.
Most coding agents are one prompt away from wandering off, looping, or shredding a file. nyxthos wraps the model in five independent systems that hold the line.
Kills doom-loops
Three identical actions and it hard-freezes, wipes the loop from memory, and forces a brand-new strategy — no more watching an agent bang the same wall.
Nothing is unrecoverable
Every write is a micro-commit on a hidden branch. Visual diffs, one-command rollback. The agent can't destroy what a keystroke can restore.
Spends tokens like they cost money
Sends only what matters — changed files, error traces, the task log — and prunes the rest before it ever reaches your budget.
Zero-config isolation
Tool commands run confined to the workspace. API keys and secrets are scrubbed from the environment and brokered at spawn — never in a log, never in a transcript.
No vendor lock-in
Bring your own model.
nyxthos never drives one company's model for you. Point it at a local runtime or a hosted endpoint, drop in an API key, and it speaks the protocol — native function-calling when the model supports it, a tagged-text fallback when it doesn't.
Ollama
vLLM
LM Studio
llama.cpp
OpenRouter
Groq
Together
Fireworks
DeepInfra
Hugging Face
Replicate
RunPod
Anyscale
Lambda
any OpenAI-compatible
Get started
One command, then nyxthos.
Install the CLI, run it in any project directory, and it opens straight into a fullscreen terminal app. On first run it walks you through choosing a model provider.
$ curl -fsSL https://nyxthos.com/install.sh | sh
# checks for Node 20+, installs the CLI — that's it
# — or with your package manager —
$ npm install -g nyxthos
$ nyxthos
# opens the TUI in the current directory
# — or build from source —
$ git clone GITHUB_URL && cd nyxthos && pnpm install &&
pnpm build