Is Fable 5.1 the new Opus 5? Within the past week, I started to notice Fable 5.1 started to get worse and worse where it starts to act like the infamous Opus 5. I had some great work completed when it came out, but there was a shift to the negative. Same thing happened to Fable 5 when Fable 5.1 was released. So, today I had Fable 5.1 try to manage another session with Fable 5.1 on processing semi-unstructured data, which is existing work in progress that already had successful sessions, so Fable 5.1 had reference data (gold data), previous handoffs, guides, etc. Both on medium effort, Fable 5.1 couldn’t harness the 2nd Fable 5.1 from bypassing guardrails , entering tables and folders it was told not to enter, and from fixating on momentum over accuracy & quality. This is Opus 5 level of bypassing prompts and guardrails from the first step. For the first time using either Fable 5 or Fable 5.1, I had to put back hooks. For context, before Fable 5.1, in order to work with Fable 5 I deleted my claude.md, memory, and more. I removed most hooks and together with Fable 5 created subagents using Opus 4.8. This for the most part worked well, it was slower with Opus 4.8, but worked for lower reasoning tasks and I didn’t have the hidden actions that drifted beyond the scope of work. After, shelling out for 20x monthly subscription, wasting more days on contaminated data and having to go back to clean it up, buying another GPU at these stupid prices is starting to sound more appealing for local AI with some fine tuning for the data I’m processing. Recently, I’ve been using Codex with Astra and it just does the work. Astra asks clear questions before starting the tasks and will pause to surface data clashes or ambiguities. Unlike Claude which will dive in head first spending tens of thousands of tokens based on wrong assumptions, and then hedge with wordiness answers after from its known errors are called out. It might be time to move up to the Codex 20x plan. How have you kept Claude within borders and from drifting with non-fully-structured data? submitted by /u/knowenuf_nada12
Originally posted by u/knowenuf_nada12 on r/ClaudeCode