3600LABS / AI LAB · FIELD NOTESEXPERIMENTS · WRITING · OPEN-SOURCE · UPDATED WEEKLY
◆ AI LAB · ISSUE №14 · MAY 2026

What we're
shipping & breaking.

Field notes from real builds, opinions you can disagree with, and the occasional open-source drop. No "ultimate guide to prompt engineering" trash. Just what we've learned this month.

★ FEATURED · 24 MAY 20268 MIN READ

Giving an AI agent tools - without burning your hand.

Most "agent" demos collapse the moment they touch a real API. Here's the small set of patterns - sandboxes, allow-lists, approval gates, and deterministic fallback - that we use to ship production agents that don't go sideways.

AI AGENTS · TOOL-USE · PRODUCTIONRead field note →
19 MAY 20266 MIN

RAG that actually answers the question.

Why most knowledge-base bots are bad - and the boring infrastructure (chunking, re-ranking, per-tenant data) that makes them good.

RAG · Read →
11 MAY 20265 MIN

A WhatsApp AI for the corner store.

The unglamorous architecture behind an assistant that handles enquiries, bookings, and follow-ups on the world's most-used app. India edition.

VOICE AI · Read →
02 MAY 20264 MIN

Invoice processing without the OCR pain.

Multimodal models flipped the playbook in 2025. Here's a pipeline you can stand up over a weekend - including the human-review step you'll forget.

DOC INTEL · Read →
27 APR 20267 MIN

Voice AI for appointments: the latency budget.

Every millisecond between user-stop-talking and bot-start-talking matters. The architecture we use to stay under 400ms end-to-end.

VOICE AI · Read →
★ OPEN SOURCE · 21 APR 2026RELEASED

prompt-gym - a tiny eval harness we use on every project.

A 200-line library to run regression tests on prompts and agent runs. Catches the "this used to work" failures before they hit production. MIT licensed.

github.com/3600labs/prompt-gym★ 1.2k · Star on GitHub →
15 APR 20266 MIN

AI agents vs chatbots: what businesses actually need.

The taxonomy that helps us recommend the right thing to clients - and stops them from buying an "agent platform" they don't need.

AI AGENTS · Read →
08 APR 20265 MIN

Sales follow-up agents: 12 patterns that work.

From cold lead nurture to closed-won onboarding. The flows we've shipped, the ones that flopped, and what makes the difference.

AI AGENTS · Read →
01 APR 20263 MIN

Why we still write SQL by hand.

Yes, the LLM could do it. We don't let it. A small rant on engineering hygiene.

OPINION · Read →
25 MAR 20269 MIN

The internal-tools renaissance.

Why your team's most-used software in 2027 won't have a Hacker News thread. And why we love it.

OPS · Read →
18 MAR 20264 MIN

What an FDE actually does in week one.

Hour-by-hour from one of our Forward Deployed Engineers, fresh from a 3-week warehouse deployment. Not glamorous. Effective.

★ FDE · Read →
10 MAR 20265 MIN

Choosing your AI vendor in 2026.

OpenAI vs Anthropic vs Gemini vs open-source. The framework we use to pick - and when we mix.

ADVISORY · Read →
◆ FIELD NOTES · WEEKLY

One field note in your inbox.
Every Friday.

Practical writing from the team - what we shipped this week, what broke, what surprised us. About 1,200 words. No motivational quotes, no "5 ways AI will change X."

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