[Bug] Claude 3.5 Opus performance regression: context loss and reduced rule compliance vs previous version

Bug Description
Opus 4.7 medium is SEVERELY underperforming Opus 4.6 Medium effort. Opus 4.6 is better at rule following, and compliant with my harness and checking the facts before giving me an answer...Opus 4.7 guesses a lot and makes very very wild swings to a point that it is non functional for my use. It is forgeting bits of context from two or three conversational turns away that is very dangerous for multi step work. I have reverted to Opus 4.6 right now...4.7 is not usable for me.

Environment Info

• Platform: darwin
• Terminal: Apple_Terminal
• Version: 2.1.118
• Feedback ID: c8257bf7-c724-4acb-bedb-5817c7f245fe

Errors

[{"error":"AxiosError: timeout of 5000ms exceeded\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:115:13291)\n    at emit (node:events:92:22)\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:114:3321)\n    at request (/$bunfs/root/src/entrypoints/cli.js:117:2467)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-24T00:08:42.266Z"},{"error":"Error: Tool SendMessage not found\n    at m57 (/$bunfs/root/src/entrypoints/cli.js:3093:31285)\n    at qJ (/$bunfs/root/src/entrypoints/cli.js:478:21013)\n    at $A (/$bunfs/root/src/entrypoints/cli.js:478:39566)\n    at Wd (/$bunfs/root/src/entrypoints/cli.js:478:50271)\n    at WRH (/$bunfs/root/src/entrypoints/cli.js:478:86947)\n    at nFH (/$bunfs/root/src/entrypoints/cli.js:478:85908)\n    at lFH (/$bunfs/root/src/entrypoints/cli.js:478:85729)\n    at Rp (/$bunfs/root/src/entrypoints/cli.js:478:82083)\n    at tH (/$bunfs/root/src/entrypoints/cli.js:478:6491)\n    at NH (/$bunfs/root/src/entrypoints/cli.js:478:4977)","timestamp":"2026-04-24T00:10:05.413Z"},{"error":"Error: Tool SendMessage not found\n    at m57 (/$bunfs/root/src/entrypoints/cli.js:3093:31285)\n    at qJ (/$bunfs/root/src/entrypoints/cli.js:478:21013)\n    at $A (/$bunfs/root/src/entrypoints/cli.js:478:39566)\n    at Wd (/$bunfs/root/src/entrypoints/cli.js:478:50271)\n    at WRH (/$bunfs/root/src/entrypoints/cli.js:478:86947)\n    at nFH (/$bunfs/root/src/entrypoints/cli.js:478:85908)\n    at lFH (/$bunfs/root/src/entrypoints/cli.js:478:85729)\n    at Rp (/$bunfs/root/src/entrypoints/cli.js:478:82083)\n    at tH (/$bunfs/root/src/entrypoints/cli.js:478:6491)\n    at NH (/$bunfs/root/src/entrypoints/cli.js:478:4977)","timestamp":"2026-04-24T00:10:17.673Z"},{"error":"AxiosError: timeout of 5000ms exceeded\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:115:13291)\n    at emit (node:events:92:22)\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:114:3321)\n    at request (/$bunfs/root/src/entrypoints/cli.js:117:2467)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-24T00:15:02.485Z"},{"error":"AxiosError: timeout of 5000ms exceeded\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:115:13291)\n    at emit (node:events:92:22)\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:114:3321)\n    at request (/$bunfs/root/src/entrypoints/cli.js:117:2467)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-24T00:15:23.203Z"},{"error":"AxiosError: timeout of 5000ms exceeded\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:115:13291)\n    at emit (node:events:92:22)\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:114:3321)\n    at request (/$bunfs/root/src/entrypoints/cli.js:117:2467)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-24T00:17:59.646Z"},{"error":"AxiosError: timeout of 5000ms exceeded\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:115:13291)\n    at emit (node:events:92:22)\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:114:3321)\n    at request (/$bunfs/root/src/entrypoints/cli.js:117:2467)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-24T00:19:26.764Z"},{"error":"AxiosError: timeout of 5000ms exceeded\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:115:13291)\n    at emit (node:events:92:22)\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:114:3321)\n    at request (/$bunfs/root/src/entrypoints/cli.js:117:2467)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-24T00:20:36.648Z"},{"error":"AxiosError: timeout of 5000ms exceeded\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:115:13291)\n    at emit (node:events:92:22)\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:114:3321)\n    at request (/$bunfs/root/src/entrypoints/cli.js:117:2467)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-24T00:32:56.123Z"},{"error":"Error: File does not exist. Note: your current working directory is /Users/zio…

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