[Bug] Sonnet 4.5 context window fills up prematurely with large files

Bug Description
Hi Anthropic team,

I’m a heavy daily user of Claude Code and pay for the highest-tier plan (over $200/month). Recently I’ve been running into two major issues:

1. Sonnet 4.5 Context Size – The context window feels extremely limited. It fills up almost instantly, especially when working with documentation or README files. I understand that large files consume context, but the limit seems much smaller than before and it’s becoming a real workflow blocker.
2. False “Approaching Weekly Limits” Warnings – Every time I start Opus in CC, I immediately get a yellow “Approaching Weekly Limits” message — even when my usage dashboard shows only ~1% used at the beginning of the week. This creates confusion and makes it hard to rely on the tool for ongoing projects.

I love Claude and use it extensively, but these two issues are really hurting productivity.

Thanks for taking a look!
— Dennis

Environment Info

• Platform: darwin
• Terminal: vscode
• Version: 2.0.36
• Feedback ID: 545e64d1-45d7-420a-b860-55136e18bc7a

Errors

[{"error":"Error: Language not supported while highlighting code, falling back to markdown: \n    at oJ (/$bunfs/root/claude:1003:4395)\n    at <anonymous> (/$bunfs/root/claude:1003:4117)\n    at map (native:1:11)\n    at CI (/$bunfs/root/claude:1003:4109)\n    at fQB (/$bunfs/root/claude:1687:6605)\n    at B7 (/$bunfs/root/claude:101:19663)\n    at T2 (/$bunfs/root/claude:103:42806)\n    at rF (/$bunfs/root/claude:103:38344)\n    at c1 (/$bunfs/root/claude:103:38272)\n    at ZJ (/$bunfs/root/claude:103:38126)","timestamp":"2025-11-09T12:00:15.407Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: \n    at oJ (/$bunfs/root/claude:1003:4395)\n    at <anonymous> (/$bunfs/root/claude:1003:4117)\n    at map (native:1:11)\n    at CI (/$bunfs/root/claude:1003:4109)\n    at fQB (/$bunfs/root/claude:1687:6605)\n    at B7 (/$bunfs/root/claude:101:19663)\n    at T2 (/$bunfs/root/claude:103:42806)\n    at rF (/$bunfs/root/claude:103:38344)\n    at c1 (/$bunfs/root/claude:103:38272)\n    at ZJ (/$bunfs/root/claude:103:38126)","timestamp":"2025-11-09T12:00:15.408Z"},{"error":"Error: Language not supported while highlighting code, falling back to markdown: \n    at oJ (/$bunfs/root/claude:1003:4395)\n    at <anonymous> (/$bunfs/root/claude:1003:4117)\n    at map (native:1:11)\n    at CI (/$bunfs/root/claude:1003:4109)\n    at fQB (/$bunfs/root/claude:1687:6605)\n    at B7 (/$bunfs/root/claude:101:19663)\n    at T2 (/$bunfs/root/claude:103:42806)\n    at rF (/$bunfs/root/claude:103:38344)\n    at c1 (/$bunfs/root/claude:103:38272)\n    at ZJ (/$bunfs/root/claude:103:38126)","timestamp":"2025-11-09T12:00:15.409Z"},{"error":"Error: Lock file is already being held\n    at <anonymous> (/$bunfs/root/claude:82:11838)\n    at O (/$bunfs/root/claude:81:5167)\n    at <anonymous> (node:fs:243:13)\n    at processTicksAndRejections (native:7:39)","timestamp":"2025-11-09T12:00:53.506Z"},{"error":"Error: Lock file is already being held\n    at <anonymous> (/$bunfs/root/claude:82:11838)\n    at O (/$bunfs/root/claude:81:5167)\n    at <anonymous> (node:fs:243:13)\n    at processTicksAndRejections (native:7:39)","timestamp":"2025-11-09T12:17:56.499Z"},{"error":"Error: EISDIR: illegal operation on a directory, read\n    at readFileSync (unknown)\n    at readFileSync (/$bunfs/root/claude:12:370)\n    at E6B (/$bunfs/root/claude:3754:768)\n    at call (/$bunfs/root/claude:1587:969)\n    at BK (/$bunfs/root/claude:1587:3002)\n    at BK (/$bunfs/root/claude:1587:3068)\n    at <anonymous> (/$bunfs/root/claude:3592:1430)\n    at processTicksAndRejections (native:7:39)","timestamp":"2025-11-09T12:22:54.035Z"},{"error":"Error: Could not load the \"sharp\" module using the darwin-arm64 runtime\nPossible solutions:\n- Ensure optional dependencies can be installed:\n    npm install --include=optional sharp\n- Ensure your package manager supports multi-platform installation:\n    See https://sharp.pixelplumbing.com/install#cross-platform\n- Add platform-specific dependencies:\n    npm install --os=darwin --cpu=arm64 sharp\n- Consult the installation documentation:\n    See https://sharp.pixelplumbing.com/install\n    at <anonymous> (/$bunfs/root/claude:228:36615)\n    at <anonymous> (/$bunfs/root/claude:11:356)\n    at <anonymous> (/$bunfs/root/claude:229:88)\n    at <anonymous> (/$bunfs/root/claude:11:356)\n    at <anonymous> (/$bunfs/root/claude:229:79804)\n    at <anonymous> (/$bunfs/root/claude:11:356)\n    at <anonymous> (/$bunfs/root/claude:229:79980)\n    at processTicksAndRejections (native:7:39)","ti

Note: Error logs were truncated.