[Bug] Claude 3.5 Opus hallucinating code solutions with high effort mode enabled

Bug Description
this has been and extremely fraustrating experience dealing with completely guess work that opus 4.6 on high effort does, hallucinating every single step of the work. i don't understand how this is something worthwhile

this is has been iteratively become worse and worse over the last month and it's now completely unreliable.

Environment Info

• Platform: darwin
• Terminal: iTerm.app
• Version: 2.1.72
• Feedback ID: 430e4c2d-ef3d-4412-b7b4-7e1983f2c76b

Errors

[{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/user/.local/share/claude/versions/2.1.72 (expected in multi-process scenarios)\n    at byT (/$bunfs/root/src/entrypoints/cli.js:2612:2025)\n    at kEq (/$bunfs/root/src/entrypoints/cli.js:2612:1169)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-03-11T08:10:38.366Z"},{"error":"Error\n    at JI (/$bunfs/root/src/entrypoints/cli.js:74:1144)\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:79:10005)\n    at emit (node:events:92:22)\n    at endReadableNT (internal:streams/readable:861:50)\n    at processTicksAndRejections (native:7:39)\n    at request (/$bunfs/root/src/entrypoints/cli.js:81:2149)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-03-11T08:10:38.836Z"},{"error":"Error: EISDIR: illegal operation on a directory, read '/Users/user/Projects/prj/.claude/tools/docs-store/docs-mcp-server/src/store/embeddings'\n    at $J_ (/$bunfs/root/src/entrypoints/cli.js:1338:111)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-03-11T09:09:19.676Z"},{"error":"Error: Request was aborted.\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:341:3940)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-03-11T10:09:59.253Z"}]