your AGENTS.md is probably 400 lines too long claude and codex skim it just like you do keep it short and it might actually follow the rules
Curated tech posts from X on AI, startups, and product development—signal without the doomscroll, updated on weekdays.
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Drawn from 161 eligible posts by 56 tracked authors.
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@aakashgupta
“After 3 minutes and 28 seconds, it had a working issue tracker running, which I named Fieldwork”
@ycombinator
“building working prototypes directly with tools like Codex”
@rileybrown
“Small tasks my dot does it, longer tasks I ask it to spin up a codex session”
@alliekmiller
“take the most boring 20-minute browser task you do every week (preferably medium value, zero-to-low risk) and hand it to a computer use agent (I prefer Codex). Record a skill for it.”
@svpino
“Your coding agent writes Python code to control the scene”
@dotta
“here's the template from the codex docs: /goal <desired end state> verified by <specific evidence> while preserving <constraints>”
@mvanhorn
“reverse-engineering their AC by having Codex watch an emulator's network calls”
@packym
“fed Codex the epub and asked it to catalog everything, put it on a timeline, make connections, etc”
@aakashgupta
“Its first self-check failed, but it fixed the check and reran it itself”
@rileybrown
“Codex is a feature inside ChatGPT.”
@weswinder
“reading all the long responses is exhausting”
@pmitu
“you switch from Claude Code to Codex, and suddenly you're onboarding a new developer again”
@emollick
“the suggestions from Codex Composer Text Predictions are always wrong”
@clairevo
“codex just typed in flora to its own embedded AI, that embedded AI called another embedded AI, that embedded AI made a call to GPT Images 2”
@cremieuxrecueil
“It seems to pre-prepare the same annoyed comments I would make”
@theo
“I burned ~$400k of Codex tokens and got nowhere”
@alliekmiller
“Claude leads on models and behavior and Codex leads on features and modalities”
@weswinder
“claude max feels unlimited for the same price”
@rileybrown
“cursor is very expensive when using frontier models compared to codex and Claude”
@corbin_braun
“codex is great but cursor really knows how to use subagents.”
@clairevo
“I can’t press “steer” anymore in codex”
@ryancarson
“Local dev is like banging rocks together and grunting versus being on a rocket. Seriously, just pay the money for something like @DevinAI”
@itsolelehmann
“stuff that Codex and Claude Code get stuck on, Grok Bot just seems to handle with much less friction”
Mixed reception.
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your AGENTS.md is probably 400 lines too long claude and codex skim it just like you do keep it short and it might actually follow the rules
My dream AI agent tool: - Opus 5.5 Level Model (never delegates to worse) - Spins up cloud and local code sessions - Dots level real time voice / tool use - Codex level Computer use on local sessions - Claude Artifacts quality decks, docs and design - Mobile app is UI of duet - Inline mini apps (What Grokbot is doing with email and slack, but do this with alot more tools) - Webhooks (Like Grokbot has) - Built in social media access across all platforms - Plugins (of course) In summary: I want an always on, frontier model powered employee that can use its own computer, and can use my computer 24/7 that self organizes all of its tasks into channels so that its easy to keep track of all the things we've done together. And I want to be able to control this agent on mobile, web, desktop, and most importantly real time voice.
most people on Earth have never heard of either Claude or Codex damn
So should Terra be the default for Codex now instead of Sol?
Berlin’s AI scene is on fire Some thoughts after OpenAI Berlin DevDays: - met so many cracked people there especially from Poland (based Poland btw, so obvious they are just killing it rn in Europe) - OpenAI seems to really care about feedback from the community about their products (keep spamming them on X about what you want, they actually care) - everyone is soooo frustrated that we can’t use any of the personal agent tools in the EU right now (they said soon though lol) - the security incidents are making ripples, it’s really top of mind for everyone - everyone technical has SO many questions about AI + GTM. if you’re a marketer and know how to use tools like codex you’re in a great position - the Berlin Ecosystem is hot right now, people seem very optimistic and lots of people are building cool shit - I went out and had some horrible food only to come back to them serving my favorite food there, tacos 😭😭 - people just love small stupid things like creating your own little codex pet cards, lol ( see pic, pretty cute ngl) - more and more people understand that creating media is as valuable as creating products, it’s really shifted in over the last few months (and after the TBPB acquisition) I’m now omw to a one day retreat with 10 other creators and people building AI companies Will report more 🫡
OpenAI's James Sun and Ari Weinstein on the AI adoption gap between San Francisco and the average American business, and why agentic computer use is the way to bridge it: "Living in San Francisco, we see a lot of thinking, 'Wow, the labs can do everything,' and, 'Why doesn't everybody just install Codex and just have it do stuff?'" "But for the average American and the average small to medium business owner or the average enterprise, even understanding what the tools are capable is [hurdle] one, connecting tools in a way that makes sense is two, deploying it is three, servicing is four." "The really cool thing about computer use as a technology is the universality of it. It works with every application. It's unlike any other thing that we've built where the developer has to do some work to adopt it, someone has to build a connector or MCP server." "If there are complex workflows that require a lot of disparate software, computer use is a great way to join them, complete the entire end-to-end workflow, and then building it in a format and UI that feels good to hold for those customers feels still like a really, really big opportunity that I think is still open." @JamesZmSun @AriX
GPT-6.1 Terra means business. Our new fast, efficient model pairs sharper visual reasoning and precise computer use with clearer, more natural writing. From decoding technical drawings to drafting proposals, filling forms to editing videos—it’s built for the whole workday. GPT-6.1 Terra is rolling out today to Plus, Pro, Enterprise, and Edu users in ChatGPT Work and Codex.
What moats are left in software? I rebuilt Linear's core from its public docs to find out. Amjad Masad, the CEO of Replit, just called out a trend we have to talk about. People are reverse engineering Adobe products. Decompiling GTA V to run it on different devices. His post hit 1.3M views: pretty soon all software will be de facto open source. AI is "coming for everything and everyone." So the question you should be asking is: what moats are really left in software? I know you don't have time to test it out, so I did. I picked Linear, the issue tracker most software teams live in. Its terms ban reverse engineering, and they've been a sponsor of mine before. So I did a clean-room build, which means I made a copy without ever seeing the original's code. I started by writing a one-page spec, using only Linear's public docs and what I already knew about Linear. Then I handed it to Codex. Codex never saw Linear's code or app. After 3 minutes and 28 seconds, it had a working issue tracker running, which I named Fieldwork. It had 5 statuses, priorities, drag and drop and Cmd+K. It all worked. There was one small flaw. Its first self-check failed, but it fixed the check and reran it itself. Then the sandbox blocked a browser, so I had to open Fieldwork in my own browser. In the end I had a pretty functioning board for this part of Linear. It didn't replicate the whole product, but it did the part I needed. Linear is valued at roughly $2.5 billion and powers 40K+ organizations. Back in February, someone cloned its core in "a couple of evenings" with about 20 prompts. So the big question is what this means for software and software valuations. Look at Adobe. Its stock is down about 26% over the last 12 months, but its ARR still grew 11% to $27.5B. And an open-source Photoshop rebuild, PhotoCraft, went viral on X. So is it going to eat up Photoshop? Does Adobe have a moat? Look at what Fieldwork didn't have. Your team's whole history of issues. The people already inside Linear. The GitHub sync that moves an issue when a PR opens. Integrations with Slack, Figma and Sentry. A copy can match your screens but it can't download your users. Which feature of yours could an agent copy from a one-page spec this afternoon? A copy can match your screens. It can't download your users.
as a counter to anthropic s1 glaze majority of q2 was the height of tokenmaxxing where companies were spending as much money as possible on credits it wasn’t until july where the idea of managing ai spend started to get traction also q2 was peak Opus 4.7 & Mythos/Fable season hype vs GPT-5.5, and Codex didn’t really take over until 5.6 during the summer i love anthropic’s products though and probably will slam the ipo because it’s first pure play ai lab but the belief that the headwinds for the ai trade have disappeared because of this document is not accurate >models have never been more commoditized than they are right now i used to be able to tell the difference between model outputs, now it’s almost impossible the more they get commoditized, the more the margins compress. this was not clear in q2. it is now. >still no clear proof of how ai drives more profit to most businesses most of anthropic’s biggest customers are publicly traded companies & they will be incentivized to decrease their own Claude spend to improve their own margins >capex commitments already signed until 2034 every hyperscaler & lab has been racing to sign deals spanning the next decade. this is all priced in already. this means the labs/mag7 basically either find ways to make existing chips more efficient (deepseek deepinfer type stuff) or they dilute shares to spend more on capex. either way stocks go down in both those scenarios — i am an ai bull but i believe the winners have still not been decided i think muse is great but does anyone know if it can drive hundreds of billions of dollars in value to Meta? well that’s what’s priced in and that’s what it would take for the investment to be worthwhile. — of course a lot can change but it feels like the real ai trade will take place after this current one settles down the real one will take time, just don’t see how it’s going to be this business cycle
You can run this app on your computer to get access to a workspace where an agent completes tasks for you. This works like LEGO: you can combine your favorite pieces to build your agent. Octop can hand off coding tasks to Claude Code, Codex, Cursor, or OpenCode. You can also use any cloud or local model. It supports browser automation, terminal access, and remote desktop.
Marvin Schwaibold leads the product design studio at Shopify, where his team is rethinking some of the company’s most important products for the AI era. Before Shopify, he co-founded the design studio Molly, working with companies including Apple and Google and building a reputation for highly crafted, interactive design. In this episode of Design Review, Marvin joins YC’s Aaron Epstein to show how AI has changed his process, from using Figma as a scratchpad to building working prototypes directly with tools like Codex. He explains why designers are becoming more like editors, how AI is making them more full-stack, and why taste and judgment matter even more when the tools can build almost anything. Then they review viewer-submitted websites and break down how hierarchy, motion, typography, and restraint can make a product feel more intentional. 00:00 — Inside Shopify’s Design Studio 00:30 — Designing With AI 01:44 — Designers Are Becoming Editors 03:25 — How Design Works at Shopify 05:58 — From Molly to Shopify 08:55 — Designing for Exploration 10:22 — Why the Details Matter 11:33 — Designing the Future at Shopify 13:24 — Prototypes Beat PRDs 15:29 — Rethinking Shopify With Sidekick 17:52 — Designers Are Becoming Builders 21:58 — Recreating Reality 24:33 — Dialing In AI-Generated Design 28:31 — Raising the Bar 31:04 — Website Review: Endstack 35:02 — SkillSync 40:49 — Instaplay 45:34 — Mintlify 51:42 — Knowlify 58:34 — Instinct Space
If I just straight up overrode the system prompt for Codex in T3 Code would y'all be upset
Reverse Engineer Anything and removing malware/spyware from your own devices sits so close to the cyber guardrails that phrasing or word choice can mean the difference between a refusal and smooth sailing. The rumors that Claude was nerfed started on reddit, and in those threads many comments point out that Claude will still do it if you rephrase it. OpenAI is treating the similar refusals with codex as accidental decision-boundary issues and says they're getting fixed. I expect Anthropic will do the same. It's pointless and counterproductive to try to restrict this. Let people do what they want with their own property. They'll do it anyway with less restrictive models, and fighting it just means losing subscriptions and a resentful public.
Unfortunately, CLI agents are no longer the ideal interface for working with agents. This has been the case for months now. It hurts to say because I have been a heavy CLI user. The reality is that new interfaces like Grok Bot, the Codex app, and others are so good that they make it easier to take advantage of the new ways to work with agents. They also make it easier to scale agent work, collaborate with complex multi-agent systems, build from anywhere, and manage the development lifecycle smoothly (with little overhead). This shift will become even more obvious in the coming months as LLMs continue to improve at things like persistence, coordination, parallelization, tool calling/MCP, memory, harness optimization, multimodal capabilities, intent understanding, UI generation, etc. The point of contact keeps getting simpler as agents continue to improve. I expect that pattern to continue. My rule of thumb now is that I don't want to use an interface that holds the model back or keeps me from leveraging it to its absolute limits.
Just realized we've pretty much maintained pace with the "28 days of improvements to Codex". We've had at least one solid improvement every day of the month. Let's make it official. Gonna ship one meaningful improvement to T3 Code every day for however long I'm capable :)
Your first four or five cold pitches will be ignored. Ankit Shukla is blunt about why, and it is not that people are busy. The work isn't good enough yet. Almost nobody says this part out loud. The standard advice treats silence as a volume problem, so send more, follow up harder, try a different subject line. He treats it as a quality signal, which is far more useful because it tells you what to change. Here's the method his students used to land roles at Meta, Amazon, Google and Sarvam AI. Build a list of 25 to 30 companies whose work you actually admire. Study them properly, not a skim of the homepage. Then answer one question: if I were the PM here, what would I do in my first six months? Then go make it. A deck, a prototype, real research. Pull emails for at least two decision makers using the free credits on Apollo or RocketReach. Send it. Follow up around three times in a week, then move on. By the fifth or sixth attempt, the replies start. Not because you got lucky on the sixth. Because five rounds of building real artifacts for real companies made the sixth one noticeably better than the first. His phrase for it is that learning is course correction. The rejections are the correction mechanism, which only works if you keep shipping new work rather than resending the same deck. The second benefit arrives later. In the interview, people talk about the projects you sent them. You stop being a candidate explaining what you'd do and become someone discussing work they've already done.
Plot twist: I’ve moved 80% of my personal coding over to claude code + opus-5.5 why? - cc projects is goated - I can’t press “steer” anymore in codex - code is good? - less front end slop but tbh: opus 5.5 creative abilities was the gateway drug to taking back my coding work
My unfiltered thoughts on personal agents. Grokbot has the best UI and it’s arguably the best overall. In a lot of ways they’re ahead. Their desktop app feels the best, and their multi-bot coordination is great: you can set a team lead and it passes tasks to the other bots. Grokbot also has the best “webhook” feature, which means you can easily turn outside events into triggers that start your agents. That speeds up background workflows like watching your email, Slack and more. It also has Cursor integration, so for bigger tasks Grokbot can spin up a Cursor cloud session with any model (until OpenAI cuts SpaceX off from their models, which I think will happen soon). Unfortunately, running frontier models through Cursor costs more than Claude or Codex. Still, they’re the only ones embracing a team of agents. It’s a really cool idea, but the more bots you have, the more time you spend managing and maintaining them. I’m starting to think one bot with different threads/channels is the right answer, which I’ll get to with Claude Duet. dots by OpenAI is rough around the edges right now, but it’s probably the most powerful if you use Codex, which I do. dots can spin up Codex sessions in the cloud or locally on your computer. So if you have coding or video editing workflows that need your local files, this is very useful. Codex computer use is also the best in the world: your dot can spin up a local Codex session that fully controls your computer, as long as it’s on. Their real-time voice is incredible. If you have your email and work tools connected, try this: go on a walk with headphones in, ask the agent to summarize your emails, have it draft replies and read them back to you, then send them off. If I remember right, this is close to a workflow you (Tim) used to have with your VAs before AI. It’s my favorite use case for personal agents. The one downside is that you have to call your agent, and it’s an awful experience. It literally rings, and it’s annoying. Muse by Meta is a toy. I’ve talked to a bunch of finance people I play poker with who all tried it and set up automations, and they all said it doesn’t reliably do what they want. It’s fast, and its user numbers will probably keep growing. But it’s basically free: you get a TON of usage without paying a dime. That’s NOT a trade I’m willing to make. An agent doing high-leverage tasks should be running at the Opus 5.5 or GPT 6.1 Sol level. Claude Duet - is in early access, so unfortunately not everyone can use it yet. First things first, it runs on Opus 5.5, the best model in the world. I’ve only had access for 72 hours, but Duet feels different from the others. It’s not a personified agent like Grokbot, dot or Muse, which gives it a more professional vibe that I like. When you ask your Duet agent to do something, it spins up a task, which is a new chat thread. All your threads show up in a Tasks tab, so it’s easy to see everything Duet is working on or has finished. And instead of creating more agents (like Grokbot), you create channels, just like Slack (I can tell @anthropic is Slack-pilled). I have a content channel, a finances channel, etc., which keeps different kinds of tasks separate. The only other app I’ve seen do this is Buzz by @jack, and it’s a good experience. Their strong point is documents (artifacts). If you want decks, high-quality docs or design mockups, Opus just wins. Period. It’s not close right now. Their weak point is real-time voice. It’s the worst of the bunch and borderline unusable, though I think they only added it a few days ago. Instinct lives in iMessage, has no app, and doesn’t do anything notable besides show you product suggestions you didn’t ask for. (Not ads, according to their team.) My hot take: The VM is overrated. SpaceX, OpenAI and Meta all talk about the VM your agent can use and feature it in their marketing. It’s not as useful as you’d think, because more and more websites block bots that visit their site on the cloud VM. All of these companies promise their agents can make payments, but most payments either take forever or get blocked altogether. SpaceX has a cool workaround with Grokbot that routes traffic through your computer so it uses your IP address. But I’d much rather the agent just USE my computer for the task, like dot does by handing it off to Codex. Also, i don't think normal people care about the virtual computer. If anything they get offended they have to "stream a computer". The problem with personal agents: by the time you read this, pick one, and test it for 7 days, every one of them will have released 10 new features and the whole landscape will have changed. It’s nearly impossible to keep up.
Every added layer of complexity in an application makes it 10x harder to describe and make content on. Back in April I was making many videos on Codex. "Codex, OpenAI's version of Claude Code" "Codex, the desktop app on your computer" "Codex, the super app that can do any CPU task" Very, very easy to describe. Repeatable, and viral. This made it effortless to describe on short form or long from videos. Then ChatGPT and Codex merged. Okay, now Codex is not an app. Codex is a feature inside ChatGPT. "Codex, the AI coding agent feature inside the ChatGPT Desktop app" Okay, now ChatGPT has "GPT Work" "Codex, the AI coding agent feature inside the ChatGPT desktop app that allows you to do coding tasks, and sometimes work tasks, some of those should be done inside GPT Work, which is kind of similar, but like different, depending on if you are using Cloud GPT Work, or local GPT work, in which case is alot closer to Codex, but still not quite the same. If you try and use the skills you created on Codex they won't work when doing a cloud GPT Work session but if it's a local session it will work." We haven't even made it to Codex Cloud sessions, GPT Dots, and GPT Plugins yet. This goes for anyone building software. If you want to create an ecosystem of creators who talk about your product organically, you should aim for simplicity. BTW not saying it was the wrong decision for OpenAI to merge them, i'm just saying for me it got much harder to describe with every new feature added.
Three of the best things to do right now related to personal cybersecurity: 1) keep all your apps and OS (computer and phone) up to date and turn on automatic updates; Amazon had OS update requirements for employees where they would shut off your systems if you were running old OS, treat it that way 2) set up 2FA/MFA and prioritize passkeys/biometrics (ie Face ID and fingerprint); second choice is authenticator app; last resort is text confirmation code and at this point, I would consider that not safe enough 3) ask codex or claude code to run a diagnostic on your personal apps and systems including public-facing artifacts (ex: website), all apps in use, api keys, etc. ask it to do research on what is happening in the world with AI attacks + don’t just review your most common apps, review ALL and ask what to do/walk you through it step by step