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Unknown hook type: Claude Agent SDK 0.3.257 Drops the Hook, Not the File (2026)
Since @anthropic-ai/claude-agent-sdk 0.3.257 a malformed hook entry is deleted from settings.json and the rest of the file loads normally, so the hook just never runs. PreToolUse and PermissionRequest are the two exceptions, where the whole file is voided. Bisected against 0.3.252, with a runnable detector.
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