[Bug] Anthropic API Error: Safeguards flagged message - reasoning_extraction

Bug Description
Fable 5 started to look at some claude session files and got this

❯ results for experiment C:
[Image #5]
[Image #5]

Excellent — the injection worked this time, and it answered BLUEBIRD: the headless turn genuinely saw the live session's transcript, by title, while the session was open, in ~3.6s. Terminal 1 showing nothing new is the expected blind spot. Before your remaining probes, let me look at the transcript on disk — it can tell us right now whether the injection landed in the same session file or forked:

Ran 1 shell command

⏺ API Error: Fable 5's safeguards flagged this message (https://www.anthropic.com/legal/aup). This sometimes happens with safe, normal conversations. Claude Code can't respond to this message with Fable 5.

Double press esc to edit your last message, or try a different model with /model.

Send feedback with /feedback or learn more: https://support.claude.com/en/articles/15363606

Details: [reasoning_extraction]

Request ID: req_011CeDUH85BtB1tfz5tZz5P7

Environment Info

• Platform: darwin
• Terminal: ghostty
• Version: 2.1.237
• Feedback ID: 55c589d7-48e9-47bd-b8cd-d18067a5743d

Errors

[]