An AI feature is a stack of five layers, not one thing to make or purchase. The decision that matters is which layer compounds your differentiation and which one a competitor can simply buy.
Agent requests don't have a stable cost — one resolves in 200 tokens, the next burns a million. Why p50 forecasts fail for agent workloads, and how to plan in token and tool-call distributions instead.
Every AI feature review argues latency, token cost, and accuracy — and never energy. Here is how to measure per-request carbon and make it a number a team owns.
Eval investment compounds like a test suite, but it shows up as cost with no revenue line — so it loses every prioritization fight to a feature with a demo. Here is how to make its counterfactual value legible to finance.
Your agent is fault-tested against timeouts and 500s, but never against a tool response that is fast, well-formed, and confidently wrong — the failure it is least equipped to catch.
Computer-use agents fail not because they ground the wrong element but because the screen moves between observation and action. A look at screen-state drift and how re-grounding fixes it.
The title 'eval engineer' didn't exist two years ago, so there's no leveling rubric and no resume that matches. Define the role around a real failure, screen for judgment over tools, source sideways from QA and platform, and write the ladder before you make the offer.
Every team wires in another MCP server, and the agent's tool surface grows with no owner, no budget, and a token tax on every turn. How sprawl breaks selection accuracy and what curation discipline fixes it.
A production incident traced back to a system prompt edited weeks earlier with no PR, no reviewer, and no owner. Why prompts keep escaping change management, and how to put them back under review without killing iteration speed.
Retry policies built for flaky networks assume the caller is correct. Agents make the caller the unreliable part, and a blind retry quietly launders real bugs into green checkmarks.
Synthetic data generated to fill dataset gaps quietly contracts toward the mean, erasing the rare cases you needed. Why per-example quality checks miss it, how to measure set-level diversity, and how to anchor generation to real data.
The line that sets your context window split — history versus retrieval versus tool output — is a product decision hiding in an f-string. Here is how to surface it, measure it, and give it an owner.