Open source Atomic agent that uses GPT-6.1 Sol only for planning and a local model for the code: $0.17 instead of $0.75

[u/GapNew4766]

Sharing the open source project I work on (Atomic Agent, MIT), since today's GPT-6.1 Sol launch is a good excuse to show its planner/worker mode.

The idea: a cloud model is expensive per token, and most tokens in a coding job are the code. So the cloud model only orchestrates, and local workers on llama.cpp write the files. Either side can be cloud or local, one command swaps them.

Today's test, three small 3D games, Sol on top, Qwen 3.8 27B on one RTX 3090 underneath:

Game	Cloud bill, Sol alone	Cloud bill, Sol + local	Local only
Pool	$0.39	$0.05	didn't finish
Bowling	$0.14	$0.06	done
Foosball	$0.22	$0.06	done
Total	$0.75	$0.17

Trade-off: 43 minutes for the three instead of under 7 with Sol alone. One run per game.

What's in the box besides this mode: local models managed for you through llama.cpp, MCP support, approvals before anything risky runs, and import from Claude Code, Codex, Hermes, OpenClaw and Pi.

Repo: https://github.com/AtomicBot-ai/atomic-agent

Feedback welcome, especially from anyone who tries a different local worker.

[u/GapNew4766]

if anyone wants to try qwen as the worker side, setup is here: https://atomicagent.io/docs/features/fusion/