标签：#guardrails

I watched an AI agent send 200 emails to the wrong recipients because I forgot one validation check. The emails were well written. The offers were real. The recipients were just... not our leads. That was early. I learned fast. Every agent I build now has three layers of guardrails before it touches a database or an API. Here's exactly what those layers look like and why they're non-negotiable for production. Input Validation: Your Prompt Is Not a Schema The first mistake people make is trusting the LLM to produce valid output. It won't. Not reliably. I've seen GPT-4 return a JSON key called "emial" instead of "email" in a critical pipeline. One typo, and the whole record is garbage. The fix is a strict validation layer that runs before any data reaches your system. In my AI resume tailor, I use a JSON schema with conditional presence flags. Every field that must be real has a has_* boolean guard. If the LLM tries to fabricate a phone number, the schema rejects it. const resumeSchema = z . object ({ contact : z . object ({ email : z . string (). email (), phone : z . string (). optional (), has_phone : z . boolean () }). refine ( data => { // If phone is present, the guard must be true return data . phone ? data . has_phone : ! data . has_phone }, " Phone number present but has_phone flag is false " ) }) This pattern catches hallucinations before they corrupt your database. The schema is the contract. The LLM is just a suggestion engine. Permission Scoping: Give Agents the Minimum They Need An agent should never have write access to tables it doesn't need. That sounds obvious, but I've seen production systems where a job description rewriting agent had full CRUD access to the user table. When I built the LLM scoring pipeline for a job board platform, I created separate database roles. The scoring agent only had SELECT on the job listings table and INSERT on a scoring results table. It never touched users, applications, or configuration. Even if the prompt was hijack

LLM Evaluation System Prompts Scored Rubrics Runtime Guardrails: A Practical Guide for Production Learn how to evaluate LLM outputs in production using system prompts, scored rubrics, and runtime guardrails to prevent hallucinations and ensure quality. TL;DR: To evaluate LLM outputs in production, combine system prompts that define evaluation criteria, scored rubrics using LLM-as-a-judge for dimensions like correctness and relevance, and runtime guardrails that filter or flag unsafe outputs. This approach scales better than human review, adapts via prompt changes, and catches failures that status codes miss, as seen in the Air Canada chatbot case. Why Production LLM Evaluation Demands More Than Status Codes A 200 status code only confirms the server processed the request—it says nothing about whether the generated text is factual, safe, or useful. The Air Canada chatbot that invented a non-existent bereavement discount returned perfectly valid HTTP responses, yet the hallucinated policy led to a tribunal ruling against the airline. Production evaluation must therefore separate operational health (latency, error rates) from output quality (correctness, relevance, harmlessness). Consider a typical API call that succeeds operationally but fails qualitatively: import requests response = requests . post ( " https://api.example.com/v1/chat " , json = { " model " : " gpt-4o " , " messages " : [{ " role " : " user " , " content " : " What is Air Canada ' s bereavement policy? " }]}, headers = { " Authorization " : " Bearer $KEY " } ) print ( response . status_code ) # 200 print ( response . json ()[ " choices " ][ 0 ][ " message " ][ " content " ]) # Output: "Air Canada offers full refunds for bereavement-related cancellations..." A 200 status code and a well-formed JSON body mask a completely fabricated policy. To catch this, you need a separate evaluation layer that scores the output against a rubric. LLM-as-a-judge is a common approach, using a second model to assess the

"Context bombing" tricks hacking agents into shutting down before they can do harm.

Guardrails positions itself as a populist political movement that runs on small donations from people in the trenches of the AI boom.