A new open-source tool called Claumon is bringing serious statistical muscle to Claude Code usage monitoring—and it's surprisingly elegant for something so technically deep. Created by developer fabioconcina and spotted on Hacker News, Claumon is a single-binary dashboard that tracks rate limits, token consumption, session history, and even your memory files across projects.

The Gamma Process Forecasting Engine

What sets Claumon apart from other Claude dashboards isn't just its UI—it's the forecasting engine under the hood. The tool uses an Empirical-Bayes model built on a Gamma process to predict where you'll land on rate limits at reset time. It generates an 80% credible interval for utilization projections, meaning you get a statistical range rather than a single guess. The model is refit daily from your own historical usage patterns and respects the monotone nature of consumption within any given window (utilization only goes up, after all). The full mathematical specification lives in internal/forecast/MODEL.pdf with LaTeX source available for the curious.

Session Tracking and Token Breakdown

Beyond forecasting, Claumon pulls real-time data from Claude Code's session files stored at ~/.claude/projects/. It parses JSONL session files via fsnotify watchers to give you per-session breakdowns of input/output/cache tokens, estimated API costs using current model pricing, and daily aggregates with 14-day trend charts. The activity heatmap shows token consumption by hour so you can spot your peak usage windows. Running processes get special treatment too—Claumon detects active sessions and can send SIGINT to gracefully stop them while preserving conversation state on disk.

Memory Browser With Health Scoring

The memory browser feature targets Claude Code power users who maintain CLAUDE.md files, project rules, and auto-memory indexes across multiple projects. Claumon assigns letter grades (A through F) based on freshness, structure, specificity, and connectedness to each memory file. Staleness indicators use color coding: green for today, gray under 7 days, yellow between 7-30 days, red over 30 days. The tool also surfaces broken MEMORY.md links and orphaned files that might be silently degrading your agent's context quality.

Cross-Platform Deployment

Claumon ships as a single Go binary with no external dependencies or build steps required. Prebuilt releases cover macOS (Apple Silicon and Intel), Linux x86_64, and Windows x86_64. Homebrew installation is available for macOS and Linux users via brew install fabioconcina/claumon/claumon. The tool can run as a background service on all platforms—LaunchAgent on macOS, systemd user unit on Linux, or Startup folder registration on Windows—no root or admin privileges needed anywhere.

Live Updates and Data Storage

All dashboard updates flow through Server-Sent Events (SSE), so usage gauges refresh every 2 minutes without polling and session tables update the instant .jsonl files change on disk. Historical data lives in a SQLite database at ~/.claumon/usage.db using WAL mode for concurrent reads during writes. On first startup, Claumon automatically backfills by scanning existing session files, giving you historical context from day one.

Key Takeaways

  • Gamma process forecasting with Empirical-Bayes estimation provides statistically rigorous rate limit predictions
  • Single binary deployment with zero config required—works out of the box on macOS, Linux, and Windows
  • Memory health scoring helps identify stale or disconnected Claude Code documentation
  • Live SSE updates mean you always see current usage without refreshing
  • MIT licensed open source tool from fabioconcina on GitHub

The Bottom Line

Claumon is the kind of tool that makes you wonder how you shipped Claude Code projects without it. The Gamma process forecasting isn't just marketing—it's actual statistical rigor applied to a real problem developers face daily. If you're running Claude Code at scale, this belongs in your workflow.