[Bug] Rate limit error despite low API usage when using Opus 4.6 (1m)

Bug Description

"Rate limit reached"; nowhere near usage limit however. Sessions are not particularly long-running. This has impacted all open sessions, not just any single one. I was using Opus 4.6 (1m Context). Seems to have been resolved by switching to Opus 4.6 (Default).

Environment Info

• Platform: darwin
• Terminal: ghostty
• Version: 2.1.49
• Feedback ID: 4e319a3c-d4e6-4dbb-856b-dc513b4f27b2

Errors

[{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/accipio/.local/share/claude/versions/2.1.49 (expected in multi-process scenarios)\n    at PFR (/$bunfs/root/claude:2599:2098)\n    at iyA (/$bunfs/root/claude:2599:1209)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-02-20T16:22:42.723Z"},{"error":"Error: 429 {\"type\":\"error\",\"error\":{\"type\":\"rate_limit_error\",\"message\":\"Extra usage is required for long context requests.\"},\"request_id\":\"req_011CYKdSgBj9rFLwf9ck8Hph\"}\n    at generate (/$bunfs/root/claude:262:28456)\n    at makeRequest (/$bunfs/root/claude:301:5435)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-02-20T16:22:48.419Z"}]