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kaicianflonetoday at 2:53 PM1 replyview on HN

Great read. The bilingual shadow reasoning example is especially concerning. Subtle policy shifts reshaping downstream decisions is exactly the kind of failure mode that won’t show up in a benchmark leaderboard.

My wife is trilingual, so now I’m tempted to use her as a manual red team for my own guardrail prompts.

I’m working in LLM guardrails as well, and what worries me is orchestration becoming its own failure layer. We keep assuming a single model or policy can “catch” errors. But even a 1% miss rate, when composed across multi-agent systems, cascades quickly in high-stakes domains.

I suspect we’ll see more K-LLM architectures where models are deliberately specialized, cross-checked, and policy-scored rather than assuming one frontier model can do everything. Guardrails probably need to move from static policy filters to composable decision layers with observability across languages and roles.

Appreciate you publishing the methodology and tooling openly. That’s the kind of work this space needs.


Replies

saezbaldotoday at 8:59 PM

The cascading failure point is critical. A 1% miss rate per layer in a 5-layer pipeline gives you roughly 5% end-to-end failure, and that's assuming independence. In practice the failures correlate because multilingual edge cases that bypass one guardrail tend to bypass adjacent ones too.

The observation that guardrails need to move from static policy filters to composable decision layers is exactly right. But I'd push further: the layer that matters most isn't the one checking outputs. It's the one checking authority before the action happens.

A policy filter that misses a Persian prompt injection still blocks the action if the agent doesn't hold a valid authorization token for that scope. The authorization check doesn't need to understand the content at all. It just needs to verify: does this agent have a cryptographically valid, non-exhausted capability token for this specific action?

That separates the content safety problem (hard, language-dependent, probabilistic) from the authority control problem (solvable with crypto, language-independent, deterministic). You still need both, but the structural layer catches what the probabilistic layer misses.