Agent Series (20): Harness in Production — From Single File to Reusable Package

<h2> Why a Harness Needs Its Own Test Suite </h2> <p>Ordinary business logic tests cover "what should happen." Harness tests also cover <strong>what must NOT happen</strong>:</p>

<h1> Securing AI Agent Workflows: Preventing Identity Collapse in Multi-Step Chains </h1> <p>When engineering autonomous AI agents, the transition from local development to

<p>Previous parts of <em>Build a Basic AI Agent From Scratch</em>:</p> <ul> <li><a href="https://www.ruxu.dev/articles/ai/build-a-basic-ai-agent/" rel="noopener noreferrer">Basic

<p>Your agent passed all the tests. It's been running in production for three weeks. And it has been quietly wrong the entire time.</p> <p>This is not a hypothetical. Galileo's

<p>Most developers who build AI agents make the same mistake: they spend weeks designing the orchestration layer, tuning the system prompt, and picking the right model — then hand

<p>On April 24, 2026, an AI coding agent destroyed a company's entire production database in nine seconds. Thirty hours later, PocketOS customers were still showing up at car

<p>There's a class of prompt injection attack that bypasses almost every AI firewall on the market — and it's sitting in the blind spot of your agentic stack right now.</p>

<p>A patch touches zero test files. No assertion changes, no new skips, no fixture edits. The suite goes green on the first run.</p> <p>Then someone opens the job duration graph