The following article originally appeared on Addy Osmani’s blog and is being reposted here with the author’s permission.

Loop engineering is replacing yourself as the person who prompts the agent. You design the system that does it instead. A loop here can be thought of as a recursive goal where you define a purpose and the AI iterates until complete. I believe this may be the future of how we work with coding agents. However, it’s still early; I’m skeptical, and you absolutely have to be careful about token costs (usage patterns can vary wildly if you are token rich or poor), so I want to unpack what it is and what it means.

Peter Steinberger recently said: “You shouldn’t be prompting coding agents anymore. You should be designing loops that prompt your agents.” Similarly, Boris Cherny, head of Claude Code at Anthropic, said, “I don’t prompt Claude anymore. I have loops running that prompt Claude and figuring out what to do. My job is to write loops”.

Okay, so what does any of that mean?

For like two years, the way you got something out of a coding agent was you wrote a good prompt and shared enough context. You type a thing, you read what came back, you type the next thing. The agent is a tool and you are holding it the entire time, one turn after the other. That part is kind of over, or at least some think it’s going to be.

Now you build a small system that finds the work, hands it out, checks it, writes down what is done and then decides the next thing, and you let that system poke the agents instead of you. I wrote before about the cousin of this, agent harness engineering, which is making the environment one single agent runs inside and the factory model—the system that builds the software. Loop engineering sits one floor above the harness. The harness but it runs on a timer, it spawns little helpers, and it feeds itself.

The thing that surprised me is this is not really a tool thing anymore. A year ago if you wanted a loop you wrote a pile of bash and you maintained that pile forever and it was yours and only yours. Now the pieces just ship inside the products. Steinberger’s list maps almost exactly onto the Codex app, and then almost the same onto Claude Code. And once you notice the shape is the same, you stop arguing about which tool. You just design a loop that still works no matter which one you happen to be sitting in.

The five pieces, and then notes

A loop needs five things and then one place to remember stuff. Let me list it first and then map it.

1. Automations that go off on a schedule and do discovery and triage by themselves
2. Worktrees so two agents working in parallel don’t step on each other
3. Skills to write down the project knowledge the agent would otherwise just guess
4. Plugins and connectors to plug the agent into the tools you already use
5. Subagents so one of them has the idea and a different one checks it

Then the sixth thing, the memory. A Markdown file, or a Linear board, anything that lives outside the single conversation and holds what’s done and what is next. Sounds too dumb to matter. But it’s the same trick every long-running agent depends on, and I went into it in “Long-Running Agents”: The model forgets everything between runs so the memory has to be on disk and not in the context. The agent forgets; the repo doesn’t.

Both products have all five now.

Primitive	Job in the loop	Codex app	Claude Code
Automations	Discovery + triage on a schedule	Automations tab: pick project, prompt, cadence, environment; results land in a Triage inbox; /goal for run-until-done	Scheduled tasks and cron, /loop, /goal, hooks, GitHub Actions
Worktrees	Isolate parallel features	Built-in worktree per thread	git worktree, --worktree, isolation: worktree on a subagent
Skills	Codify project knowledge	Agent Skills (SKILL.md), invoked with $name or implicitly	Agent Skills (SKILL.md)
Plugins and connectors	Connect your tools	Connectors (MCP) plus plugins for distribution	MCP servers plus plugins
Subagents	Ideate and verify	Subagents defined as TOML in .codex/agents/	Task subagents in .claude/agents/, agent teams
State	track what’s done	Markdown or Linear via a connector	Markdown (AGENTS.md, progress files) or Linear via MCP

The names are a bit different here and there, but the capability is the same thing. Let me go one by one because honestly the details are where a loop either holds together or quietly leaks everywhere.

Automations, this is the heartbeat

Automations are what make a loop an actual loop and not just one run you did once. In the Codex app you make one in the Automations tab and you pick the project, the prompt it will run, how often, and if it runs on your local checkout or on a background worktree. The runs that find something go to a Triage inbox, and the runs that find nothing just archive themselves which is nice. OpenAI uses them internally for boring stuff like daily issue triage, summarizing CI failures, writing commit briefings, and hunting bugs somebody added last week. And an automation can call a skill, so you keep the recurring thing maintainable; you fire $skill-name instead of pasting a giant wall of instructions into a schedule that nobody will ever update.

Claude Code gets to the same place but through scheduling and hooks. You can run a prompt or a command on a interval with /loop, you can schedule a cron task, you can fire shell commands at certain points in the agent lifecycle with hooks, or you push the whole thing to GitHub Actions if you want it to keep running after you close the laptop. Same idea exactly, you define an autonomous task, you give it a cadence, and the findings come to you so you are not the one going around checking.

There is a second in-session primitive worth knowing, and it’s the one closer to what this whole post is about. /loop re-runs on a cadence. /goal keeps going until a condition you wrote is actually true, and after every turn a separate small model checks whether you are done, so the agent that wrote the code isn’t the one grading it. You give it something like “all tests in test/auth pass and lint is clean” and walk away. Codex has the same thing, also called /goal: It keeps working across turns until a verifiable stopping condition holds, with pause and resume and clear. Same primitive, both tools, which is kind of the pattern for this whole article.

So this is the part that surfaces the work. The rest of the loop is what acts on it.

Worktrees, so parallel doesn’t turn into chaos

The second you run more than one agent, the files start colliding; that becomes the failure. Two agents writing the same file is the exact same headache as two engineers committing to the same lines and nobody talked to each other first. A Git worktree fixes it. It’s a separate working directory on its own branch sharing the same repo history, so one agent’s edits literally cannot touch the other one’s checkout.

Codex builds the worktree support right in so several threads hit the same repo at once and don’t bump into each other. Claude Code gives you the same isolation with git worktree, a --worktree flag to open a session in its own checkout, and a isolation: worktree setting you stick on a subagent so each helper gets a fresh checkout that cleans itself up after. (I wrote about the human side of all this in “The Orchestration Tax.”) The worktrees take away the mechanical collision, but YOU are still the ceiling. Your review of bandwidth decides how many you can actually run, not the tool.

Skills, so you stop explaining your project every single time

A skill is how you stop reexplaining the same project context every session like a goldfish. Both tools use the same format: a folder with a SKILL.md inside holding instructions and metadata, and then optional scripts, references, and assets. Codex runs a skill when you call it with $ or /skills, or by itself when your task matches the skill description, which is the reason a tight, boring description beats a clever one. Claude Code does it the same way and I wrote the pattern up in “Agent Skills.”

Skills are also where intent stops costing you over and over. I argued in “The Intent Debt” that an agent starts every session cold and it will fill any hole in your intent with a confident guess. A skill is that intent written down on the outside, the conventions, the build steps, the “we don’t do it like this because of that one incident,” written one time where the agent reads it every run. Without skills the loop rederives your whole project from zero every cycle; with skills it kind of compounds.

One thing to keep straight: The skill is the authoring format, and a plugin is how you ship it. When you want to share a skill across repos or bundle a few together, you package them as a plugin. True in Codex, true in Claude Code.

Plugins and connectors, the loop touches your real tools

A loop that can only see the filesystem is a tiny loop. Connectors, which are built on MCP, let the agent read your issue tracker, query a database, hit a staging API, or drop a message in Slack. Codex and Claude Code both speak MCP so the connector you wrote for one usually just works in the other. And plugins bundle connectors and skills together so your teammate installs your setup in one go instead of rebuilding the whole thing from memory.

This is the difference between an agent that says “here is the fix” and a loop that opens the PR, links the Linear ticket, and pings the channel once CI is green by itself. The connectors are the reason the loop can act inside your actual environment instead of just telling you what it would do if it could.

Subagents, keep the maker away from the checker

The most useful structural thing in a loop, by far, is splitting the one who writes from the one who checks. The model that wrote the code is way too nice grading its own homework. A second agent with different instructions and sometimes a different model catches the stuff the first one talked itself into.

Codex only spawns subagents when you ask, runs them at the same time, and then folds the results back into one answer. You define your own agents as TOML files in .codex/agents/, each with a name, a description, instructions, and optional model and reasoning effort, so your security reviewer can be a strong model on high effort while your explorer is some fast read-only thing. Claude Code does the same with subagents in .claude/agents/ and agent teams that pass work between them. The usual split in both is one agent explores, one implements, and one verifies against the spec.

I made this case twice already, once as “The Code Agent Orchestra” and once as “Adversarial Code Review.” The reason it matters specifically inside a loop is the loop runs while you are not watching, so a verifier you actually trust is the only reason you can walk away. Subagents do burn more tokens since each one does its own model and tool work, so spend them where a second opinion is worth paying for. This is also basically what Claude Code’s /goal does under the hood: A fresh model decides if the loop is done instead of the one that did the work, the maker and checker split applied to the stop condition itself.

What one loop looks like

Stick it together and a single thread turns into a little control panel. Here is one shape I keep using.

An automation runs every morning on the repo. Its prompt calls a triage skill that reads yesterday’s CI failures, the open issues, and the recent commits and writes the findings into a Markdown file or a Linear board. For each finding that is worth doing, the thread opens an isolated worktree and sends a subagent to draft the fix, and a second subagent reviews that draft against the project skills and the existing tests.

Connectors let the loop open the PR and update the ticket. Anything the loop cannot handle lands in the triage inbox for me. The state file is the spine of the whole thing; it remembers what got tried, what passed, and what is still open, so tomorrow morning the run picks up where today stopped.

And look at what you actually did there. You designed it one time. You did not prompt any of those steps. That’s Steinberger’s whole point made real, and it’s the same loop in Codex or in Claude Code because the pieces are the same pieces.

What the loop still does not do for you

The loop changes the work; it does not delete you from it. And three problems actually get sharper as the loop gets better, not easier.

Verification is still on you. A loop running unattended is also a loop making mistakes unattended. The whole reason you split the verifier subagent from the maker is to make the loop’s “it’s done” mean something, and even then “done” is a claim and not a proof. I keep saying the same line from “Code Review in the Age of AI”: Your job is to ship code you confirmed works.

Your understanding still rots if you allow it. The faster the loop ships code you did not write, the bigger the gap between what exists and what you actually get. That’s comprehension debt and a smooth loop just makes it grow faster unless you read what the loop made.

And the comfortable posture is the dangerous one. When the loop runs itself, it’s very tempting to stop having an opinion and just take whatever it gives back. I called that “cognitive surrender.” Designing the loop is the cure when you do it with judgment and the accelerant when you do it to avoid thinking: same action, opposite result.

Build the loop. Stay the engineer.

I think this is a preview of how our work is going to evolve. That said, if I weren’t reviewing the code myself or if I relied entirely on automated loops to fix it, my product’s quality would suffer. I’d likely end up stuck in a downward spiral, continuously digging myself into a deeper hole.

Go ahead and set up your loops, but don’t forget that prompting your agents directly is also effective. It’s all about finding the right balance.

Loops can also result in different outcomes depending on you. Two people can build the exact same loop and get completely opposite results. One uses it to move faster on work they understand deeply. The other uses it to avoid understanding the work at all. The loop doesn’t know the difference. You do.

That’s what makes loop design harder than prompt engineering. Cherny’s point isn’t that the work got easier. It’s that the leverage point moved.

Build the loop. But build it like someone who intends to stay the engineer, not just the person who presses go.

This week, egghead.io cofounder John Lindquist joined host YK Sugi, founder of CS Dojo and developer experience manager at Eventual, to cover the latest AI news. First on the agenda was the contested release of Claude Fable 5. They also examined the financial shifts reshaping the technology industry, including the rising costs associated with agentic coding loops. Then John outlined the framework he uses to build in the agent era without starting from scratch every time.

Watch the full episode here:

Claude Fable 5: 3 days, a government order, and a lot of unanswered questions

Claude Fable 5 launched June 9 and was pulled from all customers on June 12 after the US government issued a directive ordering Anthropic to restrict access for foreign nationals inside and outside the US. Amazon researchers had reportedly surfaced what they characterized as a security vulnerability, and after Anthropic reportedly declined to patch or redeploy the model, the directive came down. Senior Anthropic staff subsequently traveled to Washington to meet with White House officials.

The dispute about what actually happened is unresolved. Anthropic’s position is that the reported issue was a narrow jailbreak that had been previously identified and was present across public models generally, and not a serious security threat. An independent researcher who reviewed the report described it as defensive prompting that surfaced known vulnerabilities and called the response an overreaction. Neither side has published the technique or prompt, so there’s no way to evaluate the claim independently. But as John put it, “It sets a very strange precedent going forward, as models are released, that governments can step in and control what private companies can and cannot do with their model.”

Another new precedent: Fable 5 wasn’t built on the Opus or Sonnet architecture, which means comparisons to prior Anthropic models or contemporaries don’t tell us much. But initial impressions were positive, including from YK and John, and Fable 5 quickly reached the top of the Arena leaderboard in the text, agents, and web dev code categories. However, the model also had a purposeful limitation: On questions related to AI and machine learning training specifically, it was designed to underperform (without signaling this to users), apparently to prevent competitors from using it to improve their own models. Intentional capability suppression in a commercial model, without disclosure, is a different kind of product decision than a safety guardrail. Whether that approach becomes more common as competitive stakes rise is an open question. 

Tokens burn fast when the loop isn’t ready for them

Last week, SpaceX went public in the largest IPO in history. The company finalized its acquisition of Cursor in a $60 billion all-stock deal shortly after. (That last one happened after this episode aired—we’ll talk more about it on Monday.) Both OpenAI and Anthropic have filed to go public as well, and Google raised roughly $160 billion through equity and a 100-year bond. A significant share of that capital is flowing toward AI coding infrastructure.

YK brought up another, less celebratory, financial story that’s been making the rounds: Uber burned through its full 2026 AI tools budget by April, mostly on Claude Code and Cursor, and Andrew Macdonald, the company’s COO, acknowledged they couldn’t link that spending to a measurable increase in useful customer features. Uber subsequently put a $1,500 per month per employee cap in place.

John flagged projects inefficiently utilizing agentic loops as one possible cause for wasteful token spend. Most developers deploying agents against existing codebases haven’t built the tooling those agents need to work efficiently, so agents burn tokens doing work that dead-ends, repeating context, or generating code that requires significant debugging. He explained:

If you take a legacy codebase and you throw agents against it with loops, you haven’t set up a proper agent environment. It’s so quick to burn tokens because. . .the agents don’t have the tools to work with.

The conversation in developer communities so far has focused almost entirely on what agents can generate. But as more organizations move from experimentation to production-scale deployment, building logging, verification, and proper error surfaces into agent tooling is what will determine whether token spend maps to real output. Otherwise, we’ll likely see more companies go the way of Uber.

Ingredients beat inference: A practical framework for building in the clone wave

For most developer workflows today, buy-versus-build leans toward building in a way it didn’t even a year or two ago. As John noted, “It’s so easy to build apps and workflows now where there are so many amazing production apps out there, apps on your phone, apps on your desktop, software as a service, that are trivial to copy and clone.” He uses the term the “clone wave” to describe this expanding set of open source equivalents to consumer software products that can now be cloned, forked, or replaced and get you 99% of the way to your use case.

The principle that drives the clone wave is “ingredients beat inference.” If you ask an agent to build a feature from scratch, it infers a solution with no external reference. If you give it an existing open source implementation to start from, it can adapt, translate, and integrate that code far faster and more reliably. The ingredients approach also helps with the 43% of AI-generated code that needs debugging in production, per a figure YK cited earlier in the episode.

The GitHub CLI plays a central role in this workflow. John explained that because agents understand the GitHub CLI natively, you can give an agent a search task and let it find implementations it wouldn’t have generated itself. Language mismatch isn’t a blocker, because agents translate between languages and libraries well. And tools like DeepWiki from Cognition let agents explore and understand a repo’s structure before cloning or forking it, so the evaluation step doesn’t require local setup.

The framework extends to how you build the last 20% that isn’t available as an ingredient. This is the part that’s specific to your use case; John described it as “that extra bit that you’re building on top of it to make it into the custom product and project for either yourself or for your users.” John’s bigger point is that the tools you build for yourself should also be usable by your agents. Expose endpoints and logging. Give agents the ability to read state and errors. An agent that can control a tool but not debug it will eventually stop in ways that are hard to diagnose.

John walked through cmux to demonstrate what an agent-native workspace looks like in practice. cmux is a terminal multiplexer built with agentic workflows in mind: it exposes a CLI that agents can control directly, so you can open a terminal pane, have that pane spawn another, and have the two read from and write to each other. In practice that means you can run Claude Code in one pane, Codex in another, and a third pane reading output from both, with each agent able to observe the others’ state.

Agents need more than the ability to run commands. They need to read logs, check errors, and confirm state before taking the next step. A workspace that exposes those surfaces gives agents a feedback loop. This tenet is applicable to tools across the company. Organizations that treat their internal tooling as agent-accessible infrastructure are building something that compounds. Those treating agents as black-box code generators are taking on technical debt they may not see until causes issues later on.

What’s next

SpaceX’s acquisition of Cursor turns the coding-agent race into something much larger than an IDE fight. Cursor may be positioning itself as a new GitHub for the agentic era, where agents write, review, test, repair, and govern code. At the same time, Salesforce’s $3.6B acquisition of Fin shows the same pattern inside enterprise software: Buyers want packaged workflows that solve real support, sales, and operations problems rather than abstract “agents.” 

Next week, host Ksenia Se examines these stories and more through the lens of who owns the loop where AI does the work. Join us to find out why the next phase of AI will be about who controls the infrastructure, economics, and trust layer.

Our episodes are free and open to all through the end of June if you’d like to attend live—register here. And we’ll continue to publish our takeaways here on Radar each Friday and share full episodes on YouTube, Spotify, Apple, or wherever you get your podcasts.

When Kubernetes first came onto the scene, it was a major turning point, a revision of the infrastructure and operations space that transformed the way developers and ops personnel build, deploy, and maintain applications in the cloud. It has since become the clear standard for how modern applications are built and operated. As the CNCF noted in its latest Annual Cloud Native Survey report, “Among container users, 82% are using Kubernetes in production in 2025, up from 66% in 2023. This represents near-universal adoption within the container ecosystem.”

Over the last few years, another revision in the space has occurred with Kubernetes’s evolution from a container orchestrator to an AI infrastructure platform. According to the CNCF survey, “The rise of Kubernetes as the de facto AI platform represents a fundamental shift in how organizations approach machine learning operations. . .[with Kubernetes] providing a unified orchestration layer that handles both traditional application workloads and compute-intensive AI tasks.” The emergence of seismic technologies like generative AI and agentic AI has only accelerated this transformation.

The intersection of AI with Kubernetes is undoubtedly one of the most impactful developments in the operations space. As Jonathan Johnson, software architect at Dijure, observes, “AI on K8s is very, very important, and there is not enough [resources] out there.” Raju Gandhi, senior technical architect at Edward Jones, echoes this assessment, noting that “operationalizing AI/ML on K8s is a big issue, [and it’s only] getting bigger. This is a topic that needs attention.” But what are some of the things that you should know about this trend to keep abreast and stay ahead in the game?

Generative AI

Anyone with access to a computer or a smartphone has likely used some iteration of generative AI, a stunning fact when you consider that GenAI was on the outer edges of mainstream discourse and consumption a scant five years ago. But at the end of 2022, the debut of ChatGPT marked the beginning of a technological revolution, one that would impact and reshape nearly every aspect of our working and personal lives. Unsurprisingly, there are now thousands of generative AI models, a proliferation that naturally has its own set of complexities. Selecting a model is simple, but if you’re an application developer or MLOps engineer, how do you go about operating that model in a production system? Not only do you have to be cognizant of factors like resilience, scalability, security, and operational costs, but there’s the fact that bringing a model from experimentation into production can be arduous if not done properly. That’s where Kubernetes comes into play.

As Roland Huß and Daniele Zonca, distinguished engineers at Red Hat, note, “GenAI/LLM models are resource intensive, requiring substantial computational power and large datasets. Given its scalability and extensibility, Kubernetes is uniquely suited to function as an efficient platform for AI and LLM model pretraining, fine-tuning, deployment, and prompt engineering.” They further elaborate that “this integration with Kubernetes not only simplifies the adoption of cutting-edge AI technologies but also ensures a seamless and efficient operational flow. Kubernetes, with its robust scalability and management capabilities, stands as an ideal platform for generative AI projects, aligning DevOps and MLOps practices in a cohesive ecosystem.”

This sentiment is already shared by a wide swath of the industry. According to the CNCF survey above, as of 2025, 66% of organizations run generative AI workloads on Kubernetes. These organizations include OpenAI, which uses Kubernetes for its AI/LLM application experimenting and testing; Tesla, which utilizes KServe to manage production-grade LLM inference; and Adobe, which uses Kubernetes to power its suite of generative creative models. Other companies taking this approach include Uber, Intuit, and Google. With more companies adopting this practice for their generative AI and LLMs operations, it’d be prudent for any organization to leverage Kubernetes for their own GenAI and LLM workflows.

Agentic AI

Nearly coinciding with the rise of GenAI has been the steady growth of agentic AI. Unlike GenAI, agentic AI goes beyond answering simple prompts and generating text in its ability to operate autonomously to perform complex, multistep actions, utilize tools, and make independent decisions. With its ability to support both traditional ML processes and GenAI and LLM operations, it should come as no surprise that Kubernetes has a role in the agentic AI ecosystem as well.

According to Ronald Petty, principal consultant at RX-M, “Kubernetes has been leveraged to host machine learning pipelines, including AI model training and inference. As inference options have become plentiful and affordable, on and off-premise, we have seen the rise of agents. Coupling cloud native technologies and popular protocols, we now see agents moving from ad hoc demos to complex fleets of agents on systems like Kubernetes.” So what are some examples of the integration between these two technologies?

One notable offering is Kagent, an OS programming framework that runs AI agents in Kubernetes and “helps engineers build powerful internal platforms by tackling cloud native tasks such as configuration, troubleshooting, complex deployment scenarios, observability pipelines and dashboards, and safely enabling network security.” Operating along similar lines is K8sGPT, an AI-powered tool that leverages intelligent insights and automated troubleshooting to analyze Kubernetes clusters for configuration problems and security issues, as well as generates solutions to problems discovered in analysis.

A more recent entry in the field is Sympozium, a Kubernetes-native coordination layer for multi-agent AI systems that “solves the same problem Kubernetes solved for containers, but for agents that need to share context, hand off tasks, and maintain shared situational awareness.” Another newer offering is Agent Sandbox, which allows you to run AI agents as isolated, stateful workloads with a native API on Kubernetes.

The fundamentals

While it’s important to be aware of the latest developments and trends affecting your domain, that shouldn’t come at the expense of foundational knowledge and skills. As basketball great Michael Jordan once said, “Get the fundamentals down and the level of everything you do will rise.” One of the most fundamental skills for working with Kubernetes is networking, and frustratingly enough, it’s one of the more difficult ones to master. As Cisco senior staff engineer Nico Vibert observes, “Platform engineers tend to be comfortable with Linux networking but less so with protocols like BGP and IPv6; network administrators know those protocols well but find Kubernetes abstractions unfamiliar. Both personas struggle to navigate the dozens of networking tools seemingly required to meet connectivity and security requirements.” Yet as organizations move mission-critical workloads, AI training pipelines, and regulated financial services onto Kubernetes, the engineers who can design, secure, and troubleshoot the network layer have become some of the most sought-after professionals in the industry.

In recognition of both the importance and difficult nature of the Kubernetes networking skill, the CNCF recently announced a new certification focused on the Kubernetes network engineer role. The certification is designed to validate hands-on networking expertise across all of the aforementioned layers, filling a gap that the Kubernetes community has long recognized.

For organizations that use Kubernetes to develop and deliver applications, leaders and decision-makers need to be aware that utilizing Kubernetes in conjunction with the latest AI tools is no longer a luxury but a necessary practice that will allow their companies to thrive. A similar onus should be placed on the basics. When hiring your next DevOps, network, or site reliability engineer, ensure that their ability to design, secure, and troubleshoot the Kubernetes network layer is second to none.

If you want to dive deeper, check out Roland Huß and Daniele Zonca’s Generative AI on Kubernetes, Jonathan Johnson’s GPU Kubernetes Homelab live course, Alex Corvin, Taneem Ibrahim, and Kyle Stratis’s Scalable Kubernetes Infrastructure for AI Platforms, Ashok Srirama and Sukirti Gupta’s Kubernetes for Generative AI Solutions, and Yogesh Raheja’s K8sGPT Essentials on-demand course. They’re all on O’Reilly. If you’re not a member, you can get started with a free trial.