Build Lab — field notes on building with AI

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The Lab

Before You Replace the AI, Repair the Task and the Test

ExLabel and SWE-TQ make task quality a research problem. A small team can turn that question into two separate experiments: can people understand the request, and can the grader recognize a valid answer?

The Lab · 17 min read

Before You Replace the AI, Repair the Task and the Test

Maya Chen
Product Experience Editor · Nov 1, 2026 Read the teardown →

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The Lab

Experiments published after their evidence is reviewed. ★

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04 · The Lab

Does the first agent in your directory become the boss?

YC's game experiments expose a useful product question: whether a harmless-looking roster order changes who receives evidence. A controlled routing experiment can separate that effect from authority.

Oct 30 · 16 min

cover · 2:1

04 · The Lab

Your Voice Agent Ended the Call. Did It Resolve the Problem?

Vapi's traffic splitting makes version comparisons easier. A proposed repeat-contact experiment checks whether shorter calls move unfinished work somewhere else.

Oct 28 · 17 min

cover · 2:1

04 · The Lab

WebMCP Is Enabled. Can Chinese Shoppers Find the Same Products?

A proposed paired catalog experiment separates tool availability, retrieval misses, and unsupported recommendations before an agent shopping launch.

Oct 22 · 16 min

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