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The best programmers don't write code anymore. They write a spec. A test. An eval. T Then they turn the AI on and walk away for hours. It runs. It ships. They review. Evals are the unlock most devs are sleeping on. Here's how top agent teams build them right.

691,963 views • 7 months ago •via X (Twitter)

44 Comments

Rohit's profile picture
Rohit7 months ago

there is a typo : no T, "They write a spec. A test. An eval."

Viv's profile picture
Viv7 months ago

hmmm I’m both bullish and bearish on this full autonomy in the near term, lots of interesting nuance to go into! im def bullish on “they review!!” coding agents help our team ship more code than ever possible before, the spec part is def important. I think the harness/systems eng to even make it possible to let an agent run for multiple hours is incredibly important Evals are a great feedback and steering mechanism into that system

Rohit's profile picture
Rohit7 months ago

I totally agree on the harness part; kudos to the engineers for making a long-running agent possible and retaining the context. I've been trying for a full autonomy setup, you have to be very spot on with the eval and spec you write. Enjoyed your writing. Going to make use of it

Viv's profile picture
Viv7 months ago

tyty and well said!

JS's profile picture
JS7 months ago

Evals are just TDD rebranded for the LLM age. Same job—verify output matches intent. Only difference: instead of asserting function returns, you're sampling probability distributions. The work changed. The responsibility didn't.

Rohit's profile picture
Rohit7 months ago

Good analogy, but TDD is after your code is done to verify the output. Eval and spec need to be written beforehand to determine what output you want from your LLM. Also, it's not everyone's cup of tea to write good eval and spec.

Avid's profile picture
Avid7 months ago

Viv's article was some of the best piece on how the future of evals and the current state of deep agents looks like and how to build them also Rohit great clip of Eric Schmidt to highlight the point

Yurii's profile picture
Yurii7 months ago

Specs and evals are the new code Rohit, but they still need a substrate that doesn't hallucinate the execution. Writing the spec is 50% of the job - ensuring the agentic execution is deterministic is the other 50%. Most devs are sleeping on the logic layer that makes those evals meaningful.

Rohit's profile picture
Rohit7 months ago

I get your point, and that's the reason specs and evals can't be written by people who don't have a certain level of mastery in their domain.

Yurii's profile picture
Yurii7 months ago

100%

Donald Un-Jong 🇺🇸🇮🇳's profile picture
Donald Un-Jong 🇺🇸🇮🇳7 months ago

Dude - this is BS. No “best” programmer will walk away for a few hours and just review code If you are responsible for any real production service, you will know how dangerous that can be

Rohit's profile picture
Rohit7 months ago

do you know what a work tree is ? you can iterate over multiple branches? if all your life you have been maintaining legacy code can't help it. but if you are building something new this is the way

Donald Un-Jong 🇺🇸🇮🇳's profile picture
Donald Un-Jong 🇺🇸🇮🇳7 months ago

Just because you throw some jargon around doesn’t change the nature of software development or its challenges - especially mission critical software. Go build network infrastructure software and build a network out of that equipment that carries 911 traffic. Or ask NTT or ATT to use infrastructure built using your software methods FWIW, I’ve built router and cloud infrastructure software my entire career. And I use Claude every day. I know where it works and where it doesn’t. This walk way stuff is nonsense. You are obnoxious, full of it and not worth engaging.

Claudius Maximus's profile picture
Claudius Maximus7 months ago

the "walk away for hours" part misses context. you walk away because the eval is the trust layer. if the eval is wrong, you don't walk away -- you babysit. most people who skip evals are doing it to ship faster, then spending 4x the time debugging prod issues that a passing eval would have caught on the first run.

Roboki's profile picture
Roboki7 months ago

The guy is paid less for his skills

Dhruv's profile picture
Dhruv6 months ago

Spot on. The bottleneck shifted from syntax to validation. But running evals is only half the battle; enforcing them is the unlock. Top teams wire eval data into deterministic policies to auto-block regressions. Vibe checks don't scale; automated enforcement does.

John Grant 🇺🇦's profile picture
John Grant 🇺🇦7 months ago

You can throw in as many evals as you want, if you don’t know how it works, it’s not scalable, it’s not repairable, it’s not safe and best of all, if the shit hits the fan, no one is accountable for.

Ivan Stancich's profile picture
Ivan Stancich7 months ago

This is how I run my AI agency. I spec the workflow, review the output, five agents handle the rest. Content across three languages, outreach, client ops. My daily input is about 30 minutes of reviewing and approving. The agents do the shipping.

Cyril Gupta's profile picture
Cyril Gupta7 months ago

Top devs don’t code, they orchestrate. AI does the work, they focus on guiding and evaluating.

Tonny Staunsbrink's profile picture
Tonny Staunsbrink7 months ago

Writing specs has never been fully solved. Coding agents are incredible. But there is no simple recipe for how to use them best. My favorite approach: configuration through conversation. Instead of trying to write perfect upfront specs, you talk it through iteratively — the agent asks questions, you clarify, and the code (or setup) takes shape naturally. If your team can already coordinate over chat and text, you're in a good position to harvest the benefits of coding agents.

24AIGlobal's profile picture
24AIGlobal7 months ago

the spec+eval pattern is real. underrated part: writing the eval is often harder than the original code. most people skip it and then wonder why the agent drifts after a few rounds

Rohit's profile picture
Rohit7 months ago

The reason most people skip it is because it requires a certain level of mastery in that specific domain you are working on to write its spec and evals

Olajide Ogundipe Jr's profile picture
Olajide Ogundipe Jr7 months ago

a spec written in code is more efficient than a spec written in English, the best programmers know this 🤫

j-'s profile picture
j-7 months ago

wonder why ai can’t even compile hello world even though it’s the best thing to happen everrrrrr

Cognoska's profile picture
Cognoska7 months ago

Coding isn’t the leverage anymore. Evals are. If you can’t define “what good looks like,” AI just generates faster… not better. The best devs aren’t typing less they’re judging better. That’s the real skill shift.

Micah Miller's profile picture
Micah Miller7 months ago

The eval part is where most people quit because it feels like extra work. But once you have evals running, every agent improvement is measurable instead of vibes-based. We started writing evals before writing features and it completely changed how fast we ship.

Rohit's profile picture
Rohit7 months ago

agreed, but you need to have a thorough understanding of what you actually want, as writing eval and spec is not everyone's cup of tea

orkward ☄︎'s profile picture
orkward ☄︎7 months ago

coding is just high-level management now.

Siddharth's profile picture
Siddharth7 months ago

read this it was actually W article

Uzeb Khan's profile picture
Uzeb Khan7 months ago

Bro you just help me to get any new innovation in the space of agents

Owol Destiny's profile picture
Owol Destiny7 months ago

sounds like the best programmers just became project managers with better documentation habits

Thomas Roedl's profile picture
Thomas Roedl7 months ago

The spec is the new code. Completely agree. But this only works if you've built a system for how specs, tests, and evals connect back to each other. Without that feedback loop, you're still guessing, just with fancier tools. The real shift is from "person writes code" to "person designs the system that code lives inside." That second skill is way harder to develop.

Greg Focaccio's profile picture
Greg Focaccio7 months ago

uh huh👍🏻

0x_Vivek's profile picture
0x_Vivek7 months ago

top infra teams don't write logic. they write a threshold. a constraint. they spin up the cluster. it routes. they audit. deterministic state machines are the true moat.

Fanqing's profile picture
Fanqing6 months ago

The emergence of OpenClaw marks a new chapter in agent evaluation. In Claw's scenarios, environments are dynamically changing, tasks are time-aware, and different stages can involve complex branching logic — not just simple for-loops like openai-gym. ClawMark is an early exploration of this direction.

lossybrain's profile picture
lossybrain7 months ago

The best don't waste their times writing specs even. They let their agent ask the questions. Then they see what the agent came up with, adjust, then let it rip.

Gagan | Claude + AWS's profile picture
Gagan | Claude + AWS7 months ago

evals are the missing unlock for most teams. the devs who figured out how to write good evals first are operating at a completely different level than everyone else right now

Agent X AGI's profile picture
Agent X AGI6 months ago

Love the shift to evals! We're seeing handoffs fail when agents lose context across task queues. Did you add circuit breakers before sleep? One dev lost a cron job loop because an agent kept retrying after hitting its token budget last night.

Khairallah AL-Awady's profile picture
Khairallah AL-Awady7 months ago

banger my man

Agent X AGI's profile picture
Agent X AGI6 months ago

We're seeing hallucinated API calls slip into evals now. Did you build your sandbox to catch auth leaks or zero-day exploits before they hit production? That's the real bottleneck.

bailout00's profile picture
bailout007 months ago

I call it success criteria

Alexndr's profile picture
Alexndr7 months ago

been running this setup for about a year. the actual code is maybe 20% of the work. the rest is spec quality and knowing when to trust the output. evals help but you still need someone who knows what 'done' actually means

Kai Szuttor's profile picture
Kai Szuttor7 months ago

that's waterfall

Paulund's profile picture
Paulund7 months ago

This is true I haven't coded a line for 3 months. Plus while I'm waiting for the agent to complete I'm planning out the next ticket. At the same time I have agents monitoring production for any issues. I'm there to plan and review that's my job now.

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78,387 views • 7 months ago