[Bug] Anthropic API Error: Over-aggressive content filtering blocking legitimate code review requests

Open 💬 0 comments Opened Jun 10, 2026 by nicolito

Bug Description
Fable 5 is consistently flagging queries and refusing to do mundane tasks: ❯ Could you go through the files in the Production_module_build folder and sanity check them for factual and logical errors against validated peer reviewed literature. Also add the references to the source literature
where this is motivated by context and factual claims. You have some literature in the referenser_interactive_tools folder, but may have to search the web for some claims

● I'll start by surveying the folder structure and the files to review.

Listed 1 directory (ctrl+o to expand)

● Fable 5's safety measures flagged this message for cybersecurity or biology topics. They may flag safe, normal content as well. These measures let us bring you Mythos-level capability in other areas sooner, and we're
working to refine them. Switched to Opus 4.8. Send feedback with /feedback

Environment Info

  • Platform: linux
  • Terminal: pycharm
  • Version: 2.1.170
  • Feedback ID: 22d9fc37-5667-411e-8b0b-9ce36bd88bd2

Errors

[{"error":"Error: 400 {\"type\":\"error\",\"error\":{\"type\":\"invalid_request_error\",\"message\":\"tools.10.model: 'claude-opus-4-8' cannot be used as an advisor when the request model is 'claude-fable-5'.\"},\"request_id\":\"req_011Cbu9rv1dUkAEZ3dAacPZN\"}\n    at generate (/$bunfs/root/src/entrypoints/cli.js:11:67844)\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:51:7694)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-06-10T07:04:40.596Z"}]

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