A local proxy that sits in front of your coding agent and tells you what each session actually cost, where the time went, and which optimisations would be worth anything on your traffic. Runs on your machine, uploads nothing. Beta opening now.

Local developer observability sidecar, transcript mining, and workflow skill miner for Claude Code and Antigravity. Runs 100% on your machine — track token spend, cache hits, and idle/active time with zero cloud overhead. Mines your transcripts to auto-detect repeat workflows and turns them into reusable skills. Free and open source. Built by the team behind ACE Fleet, the hosted engine for cutting production AI API costs.

Hey Product Hunt 👋 We built ACE Sidecar because we kept flying blind on our own Claude Code and Antigravity usage — no idea what our sessions actually cost, how often we were hitting cache, or which workflows we kept repeating by hand. Sidecar runs 100% locally (127.0.0.1:8787) — it watches your coding agent traffic, gives you real-time cost/token observability, and mines your transcripts to auto-detect repeated multi-step workflows so you can turn them into reusable skills. No cloud, no telemetry leaving your machine, fully open source (AGPL-3.0). It's actually a spinoff of a bigger problem we're solving at ACE Fleet — cutting AI API costs in production with caching, routing, and compression. Sidecar was born from wanting that same visibility on the local dev side, and we figured other builders would want it too, so we open-sourced it standalone. Would love feedback — especially from anyone running heavy multi-agent workflows. What would make this more useful for your setup?

ACE Sidecar

A local proxy that sits in front of your coding agent and

A local proxy that sits in front of your coding agent and

ACE Sidecar

Previous ACE Sidecar Launches

Previous ACE Sidecar Launches