I Had No Idea How Full My Claude Code Context Window Was. So I Built a Tool.

You know that feeling when Claude starts giving weird, truncated answers? Or when it seems to "forget" earlier context in a long session? That's your context window filling up. Claude Sonnet has a 200,000 token context window. When it's full, older messages get dropped. Your carefully set-up context — the files you loaded, the constraints you established, the codebase you explained — silently disappears. I've been running Claude Code for 60+ days in an autonomous loop. Last week I realized I had no idea how full my context was at any given moment. So I built cc-context-check . What it does npx cc-context-check cc-context-check — Context window usage across sessions Context limit: 200.0k tokens (Claude Sonnet/Opus) 🟢 ~/projects/my-app [a3f9c12] just now · 12.4 MB ████████████░░░░░░░░░░░░░░░░░░ 40.1% used 80.2k input · 1.2k output · 119.8k remaining 🟡 ~/ [b7d44e1] 2h ago · 5.9 MB █████████████████████░░░░░░░░░ 71.5% used 143.0k input · 89 output · 57.0k remaining △ Warning: Context is ge