I built an agent Harness for Small Models. I got Qwen 3.5 4b managing servers.

This is something I've been working on, I like playing around with smaller local models but found most agent harness's not well suited for them. The failure modes across different model family's tend to be the same:

• Failed tool calls
• Poor varication of environment variables
• Poor recovery on common failure modals
• Small model tend to pause/halt during generation with local backend
• Poor state tracking during goals
• Poor local/remote task separation

Basically the harness needs to be built around the local model. I built a harness for the qwen and gemma family of local models that does just that.

Here's the github Link

Here's Qwen 3.69b managing servers

More interesting in my opinion.

Here's qwen 3.5 4b managing remote servers in the harness

The repo explains several of the techniques used to get some of these results. If your interested please give the harness a look. I'd love to get it more stable, but I'm only one person.