As you manage a fleet of agents, you cannot manually review every output. Platforms like HyperAgent use "Rubrics"—an evaluation framework where one LLM judges another's work against predefined criteria. This automates quality control, which is essential for scaling an agent-first business.

A robust framework for measuring an AI agent's success requires a tiered approach. First, establish baseline quality (is it working correctly?). Then, measure user engagement (adoption, retention). Finally, connect these to top-line business impact (revenue, savings).

Treating AI evaluation like a final exam is a mistake. For critical enterprise systems, evaluations should be embedded at every step of an agent's workflow (e.g., after planning, before action). This is akin to unit testing in classic software development and is essential for building trustworthy, production-ready agents.

A key metric for AI coding agent performance is real-time sentiment analysis of user prompts. By measuring whether users say 'fantastic job' or 'this is not what I wanted,' teams get an immediate signal of the agent's comprehension and effectiveness, which is more telling than lagging indicators like bug counts.

Building a functional AI agent is just the starting point. The real work lies in developing a set of evaluations ("evals") to test if the agent consistently behaves as expected. Without quantifying failures and successes against a standard, you're just guessing, not iteratively improving the agent's performance.

To manage non-deterministic AI products, Shopify created an internal tool where PMs grade AI-generated outputs. This creates a "ground truth" dataset of what "good" looks like, which is then used to fine-tune a separate LLM that acts as an automated quality judge for new features and updates.

The prompts for your "LLM as a judge" evals function as a new form of PRD. They explicitly define the desired behavior, edge cases, and quality standards for your AI agent. Unlike static PRDs, these are living documents, derived from real user data and are constantly, automatically testing if the product meets its requirements.

Descript's design principle for its AI agent, Underlord, is that it can't do anything a human user can't, and vice versa. This frames the AI as a true collaborator within the existing product interface, not a separate entity with special powers.

Instead of generic benchmarks, Superhuman tests its AI models against specific problem "dimensions" like deep search and date comprehension. It uses "canonical queries," including extreme edge cases from its CEO, to ensure high quality on tasks that matter most to demanding users.