Erik Cohen

Hands-on evaluation engineering for AI agents.

I help CTOs and engineering leads evaluate customer-facing LLM agents, starting with established software products adding agents.

11+ years shipping software. Production AI since 2021. MS CS (ML), Georgia Tech, completing 2026.

In a 30-minute discovery call we cover what you're building, what's failing and which kind of help fits.

Every AI change gets inspected before it reaches your users.

Illustration.

Three places teams get stuck

Each opens a working example you can explore.

Build it right

“The demo works. Now it has to ship.”

Illustration: one voice turn, each stage in order over time.

What an agent is made of, stage by stage: retrieval, the model and, on a phone line, speech in and out.

See one call, stage by stage

Know it works

“You can't measure the vendor's demo.”

Illustration: a release gate. 23 checks pass, 1 fails, and the change waits.

When a prompt, model or provider version changes, test real tasks for regressions before customers find them.

Break the demo, watch the gate

Keep it working

“A wrong answer reached a customer.”

Illustration: answer correctness by day against a threshold. One day drops below it.

Every stage traced in production, and scripted conversations that check latency and correctness against a spec, so you see which stage regressed.

See a regression traced to its stage

Recent work

Evals for AI used by scientists

At BenchSci I owned evaluation end to end. Manual validation time fell 60%.

Read the research-assistant case study

Independent AI/ML engineering

Independent contractor (Cohen AI Consulting LLC), AI/ML engineering for a US healthcare-technology company, Jan–Oct 2026.

See one call, stage by stage

How we can work together

Two ways: an embedded AI engineer who ships features with the evaluation pipeline that measures them, or a written review of your AI system's failure modes and eval gaps. How engagements work

Start with a discovery call

Tell me what you're building, what's failing and when you need help. We'll discuss whether an engineering engagement or a written review fits.

Book a 30-minute discovery call

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