Ctrlb Decompose

Turn millions of noisy log lines into compact patterns with typed variables, quantiles, anomalies, and LLM-ready output.

Runs as a CLI, in the browser via WASM, or as a Rust library — no logs ever leave your machine.

No install, no signup — the whole pipeline (CLP encoding, Drain3 clustering, typing, stats) runs client-side in WebAssembly.

The Drain algorithm builds a prefix tree over logtypes and groups them by token similarity (configurable threshold, default 0.4). Where tokens diverge, the template gains a <*> wildcard. This runs incrementally — each line is processed once with no second pass.

Compact, token-efficient markdown designed to be pasted straight into a prompt — see the LLM OPTIMIZE screenshot above for a full real-world example against a 56K-line log.

Use ctrlb-decompose directly from Claude Code — no CLI knowledge needed. The plugin installs ctrlb-decompose automatically and lets you analyze logs just by asking.

Claude will check if ctrlb-decompose is installed (and walk you through installation if not), run the analysis, and explain the results — surfacing errors first, calling out anomalies, and suggesting what to investigate next.