Dynobox - a local CLI tool for testing AI agent skills

Hey!

I'm building https://dynobox.xyz as a local test runner for agent skills. It acts like a unit/behavior test matrix for AI agents and harnesses, with built-in regression tracking.

Write scenarios in JS/TS or YAML, run them against different local agent harnesses (Claude Code, OpenAI Codex, etc.), and compare results side-by-side.

It shines at surfacing differences across harnesses: tool calling behavior, shell commands, files modified, HTTP requests, skill invocations, and final outputs.

Saved run comparisons and cross-run diffs make it much easier to spot where one harness succeeds and another flakes or diverges (see screenshots below).

Especially useful for catching flaky behavior and hidden assumptions when moving between harnesses.

Would love feedback or to know how people are currently testing their skills!