Evidence record / grok-build
A dated record of one change, kept so the writing that cites it can be checked. Compiled from the sources listed below by the research run, not written for reading. The judgment lives in the issues that cite it, below.
2026-09-21-grok-build-hooks-gained-power-and-still-fail-open
Hooks gained power, and still fail open. Hooks can now ask, block prompts, and redact tool output before the model sees it. The failure mode did not change.
Channel: tagged-release. Half: both. Date: 2026-08-28 (1.0.13), 2026-08-31 (1.0.14), by 2026-09-19 (UserPromptSubmit blocking).
Operator consequence: A redaction or allowlist hook is a control only if it cannot crash: wrap it so every error path prints an explicit deny. In auto mode, L332 says allow rules are not a closed allowlist and the classifier can approve commands no rule mentions; use deny rules or a PreToolUse hook for hard limits.
Receipt
Finding metadata
Run: 2026-09-21-weekly-digest-2026-08-20_2026-09-21-frontier-v0
Finding ID: 2026-09-21-grok-build-hooks-gained-power-and-still-fail-open
Profile citations
- grok-build / claim / hooks-fail-open
Source links
Primary links, including exact changelog lines when available.
Versioned source: run artifact