[Bug] Fable 5 safeguards falsely flagging legitimate software engineering tasks causing model switching and API blocks

Bug Description
Subject: False-positive safeguard flags repeatedly interrupting legitimate software-engineering work (Claude Code, Fable 5)
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▎ I'm using Claude Code with Fable 5 for a legitimate internal software-engineering project: maintaining the integrity of a research documentation catalog. The work consists entirely of ordinary engineering tasks — writing Python guard scripts, verifying git commit completeness, staging/committing snapshot files, fixing manifest data, and running static-analysis gates. There is no offensive-security, malware, biological, or otherwise policy-relevant content anywhere in this work.
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▎ Problem: Fable 5's safeguards keep flagging my messages with "Fable 5's safeguards flagged this message… Switched to Opus 4.8." The forced model switches (Fable → Opus 4.8 → Fable → Opus 4.8) accumulate across turns and now culminate in a hard API error that blocks the message entirely:
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▎ API Error: Fable 5's safeguards flagged this message (…/legal/aup). … Claude Code can't respond to this message with Fable 5. Request ID: req_011CdvduQJz6WqCy73sDKpgj
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▎ Impact: (1) The repeated mid-task model switching makes the assistant's behavior inconsistent and confusing to follow. (2) The final hard block prevents work from continuing at all. (3) None of the flagged content is actually policy-relevant — these are false positives on routine coding, git, and static-analysis operations.
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▎ Request: Please review these as false positives and adjust the safeguard sensitivity for this class of legitimate coding/DevOps work. If helpful, the flagged turns involved: git commit/status operations, Python guard-script authoring (allowlist-based repo-hygiene checks), and snapshot file staging. Request ID above is a concrete example of the hard block.

Environment Info

• Platform: win32
• Terminal: null
• Version: 2.1.226
• Feedback ID: aad7ded6-b3be-4c6d-9365-498289d8e89d

Errors

[{"error":"TelemetrySafeError: VirtualMessageList: itemKeys/messages length desync (keys=613 messages=612 range=[576,613))\n    at mME (B:/~BUN/root/src/entrypoints/cli.js:23196:8181)\n    at zAm (B:/~BUN/root/src/entrypoints/cli.js:23196:1103)\n    at qi (B:/~BUN/root/src/entrypoints/cli.js:2576:21373)\n    at Dc (B:/~BUN/root/src/entrypoints/cli.js:2576:40475)\n    at ty (B:/~BUN/root/src/entrypoints/cli.js:2576:51399)\n    at bKe (B:/~BUN/root/src/entrypoints/cli.js:2576:89085)\n    at YIe (B:/~BUN/root/src/entrypoints/cli.js:2576:88029)\n    at Yre (B:/~BUN/root/src/entrypoints/cli.js:2576:87848)\n    at E1 (B:/~BUN/root/src/entrypoints/cli.js:2576:84102)\n    at vt (B:/~BUN/root/src/entrypoints/cli.js:2576:6668)","timestamp":"2026-08-11T06:02:01.718Z"}]