Tip: Stack RTK and Headroom at Different Layers to Cut Coding-Agent Token Bills ~80%

Andrew Patterson (blog)·medium signal

RTK and Headroom operate at distinct points: RTK sits between the agent and the shell (compressing per-command output 60–90%), while Headroom sits as a local API proxy compressing everything bound for the model (JSON arrays, AST-aware code, logs, RAG results, conversation history). Run both to remove noise at the source and again before the API call. RTK supports 100+ commands out of the box and applies smart filtering, grouping, truncation, and dedup.