Coding assistants have moved past autocomplete into full brokers that may learn tasks, run instructions, edit information, and iterate towards outcomes. Instruments like Claude Code and Codex each function on this house, however take completely different approaches. Claude Code facilities on a unified agent loop throughout environments, whereas Codex spreads capabilities throughout CLI, IDE extensions, cloud workflows, and delegated duties.
This isn’t about mannequin efficiency. It’s about workflow: management, intuitiveness, and the way simply you possibly can keep centered whereas working inside an actual repository. On this article, we evaluate how every device matches into the act of getting work achieved.
Getting began with Claude Code and Codex CLI
Earlier than transferring onto the actual workflows, First let’s set up each the instruments in our system. Please make certain your system has node already put in.
Codex CLI
Set up the Codex CLI with npm. Open your terminal and run
npm i -g @openai/codex
Run Codex in a terminal. It will probably examine your repository, edit information, and run instructions.
Codex
Sign up with an OpenAI account or API key
Claude Code
Set up the Claude Code with npm. Open your terminal and run
npm set up -g @anthropic-ai/claude-code
Run in terminal by altering the listing to explicit venture
claude
Sign up with an Anthropic Account
Now all set, let’s transfer to workflows.
The primary 10 minutes really feel completely different
Claude Code appears like an assisted accomplice. It needs to get a deal with on the repo, recommend a plan, then proceed with the duty with mode permission and checkpoints to maintain it protected. Codex appears like a configurable runtime. It’s nonetheless conversational, however the focus is extra on configuration, insurance policies, worktrees, overview, and cloud delegation.
If you’re opening a repo for the primary time, the hands-on distinction exhibits up instantly.
With Claude Code, a pure first transfer is:
Clarify the auth movement, record the dangerous information, and inform me the place login might be failing.
With Codex, the equal appears like:
Clarify the auth movement, record the dangerous information, and inform me the place login might be failing
The identical immediate, however the expertise could be very completely different. Claude usually encourages you to plan and execute. With Codex it feels prefer it asks you to set the parameters of freedom, sandboxing and approvals earlier than leaping in.
That distinction issues. For those who like being guided to productiveness, you’ll like Claude Code extra. For those who wish to design a system, Codex is extra rewarding.
The Translation Layer: How the ideas map?
A lot of the confusion of Claude Code vs Codex is because of completely different terminology.
Facet
Claude Code
Codex
Repo Directions
Saved in CLAUDE.md
Saved in AGENTS.md
Reminiscence
Auto reminiscence
Specific Recollections system
Session State
Checkpoints and /rewind for code and session state
Emphasis on code opinions and structured code state
Code Administration
Inline iteration with checkpoints
Worktrees and review-driven workflows
Distant Work
Distant Management resumes native periods (runs in your desktop)
Distant connections, app-server workflows, and cloud delegation by way of internet
Execution Mannequin
Native-first, session continues in your machine
Native + distant + cloud execution break up throughout environments
Agent Workflows
Helps subagents and parallel agent workflows
Specific subagent workflows with structured orchestration
Parallelism
Constructed-in parallel agent execution
Parallelism by way of worktrees and orchestrated brokers
General Method
Unified, session-centric workflow
Distributed, system-oriented workflow
That is the mannequin to bear in mind if you learn the remainder of this text.
Repo directions: CLAUDE.md vs AGENTS.md
This can be a vital a part of the article as a result of it impacts how the agent feels after the primary day.
Claude Code hundreds CLAUDE.md originally of every session and makes use of it as context for the venture, your Workflow, and even your organization. Anthropic’s documentation is evident that it’s best to use CLAUDE.md to seize the principles you don’t need to repeat, and use auto reminiscence for Claude’s studying.
The Codex answer makes use of AGENTS.md, however in a extra refined means. You possibly can have a world ~/.codex/AGENTS.md, then AGENTS.md per repo, then sub AGENTS.override.md, all as a part of the config.toml construction.
Right here’s the way it may work.
Right here’s a helpful CLAUDE.md for a Node repo:
A helpful AGENTS.md for a similar repo may appear like this:
The hands-on lesson is straightforward. Don’t wait till the agent disappoints you 5 occasions. Write the instruction file early. Each instruments get significantly better as soon as your requirements dwell within the repo as a substitute of in your head.
Reminiscence: What will get remembered and the way helpful it truly is?
The context window for Claude Code is wiped in the beginning of every session, however you possibly can load your CLAUDE.md and auto reminiscence. In response to Anthropic, auto reminiscence is notes that Claude writes primarily based in your corrections and preferences, resembling construct instructions, debugging hints and issues it has seen whereas modifying in that tree.
Codex Recollections are comparable however they’re barely extra express. Recollections are disabled by default, are saved regionally (in ~/.codex), and are for fastened preferences, frequent routines, project-specific conventions, and customary gotchas. The OpenAI docs additionally advise to not retailer recollections of guidelines as the one place for guidelines that should at all times be adopted. These nonetheless have to go in AGENTS.md or in paperwork within the repo.
This ends in an amazing workflow.
If you’re utilizing Claude Code, you possibly can have the agent be taught the tempo of the repo, then use CLAUDE.md for issues it is advisable hold secure.
If you’re utilizing Codex, don’t put the contract in Recollections. Put the contract in AGENTS.md. Put your platform guidelines in config.toml. Let recollections fill within the gaps.
This makes Codex really feel extra mechanical. Claude is extra like a wise teammate.
Permissions and planning: That is the place the character break up turns into apparent
Claude Code has very descriptive names for permission modes. The obtainable modes are at the moment default, acceptEdits, plan, auto, dontAsk, and bypassPermissions. plan is especially attention-grabbing because it permits Claude to plan and suggest adjustments with out touching your supply, and auto is a analysis preview that makes use of an additional classifier to filter actions.
Codex describes this by way of sandbox and approval coverage. OpenAI’s documentation calls sandbox mode the technical sandbox and approval coverage the rule for when to ask permission. Native Codex by default makes use of no networking and sandboxing below the OS, which is often configured by way of ~/.codex/config.toml and, optionally, project-specific .codex/config.toml.
Right here is the hands-on model.
In order for you Claude Code to examine a repo and produce a proposal earlier than touching something:
claude –permission-mode plan
In order for you Claude Code to maneuver sooner on protected file edits:
claude –permission-mode acceptEdits
In order for you Codex configured for a tighter read-only cross first, the OpenAI docs present patterns like this:
Open the .codex/config.toml file and add the next traces:
[profiles.readonly_quiet]
approval_policy = “by no means”
sandbox_mode = “read-only”
Then you should utilize that sort of profile for a first-pass audit and solely loosen up it if you end up prepared.
This distinction issues so much in actual groups. Claude exposes the protection mannequin as an interplay sample. Codex exposes it as a system configuration sample.
Let’s say your checkout take a look at is failing and also you need the agent to analyze, repair, confirm, and clarify the change.
An excellent Claude Code workflow seems like this:
Discover why the checkout is failing. Begin in plan mode, determine the smallest protected repair, implement it, run the related exams, and summarize the change in plain English.
An excellent Codex workflow seems like this:
Examine the checkout failure, hold scope minimal, clarify root trigger first, then patch solely the information required, run the smallest related take a look at set, and present me the diff I ought to overview.
Discover the distinction. With Claude Code, you naturally lean into movement. With Codex, you naturally lean into express scope and overview language.
Each instruments can do the loop, however they encourage barely completely different kinds of prompting.
Undo, restoration, and reviewing adjustments
Claude Code’s undo/rewind is a strong characteristic. Anthropic claims that each user-prompted change makes a checkpoint, the checkpoints are persistent, and /rewind can restore code, dialog, or each. So you possibly can “experiment” extra with out worrying about errors.
A “actual” use case seems like this:
/rewind
You then select whether or not to simply rewind the code, simply the chat, each, or begin summarising from a specific level and proceed.
And Codex addresses security in one other means. The overview pane shows the adjustments within the repo, means that you can add inline feedback and to stage, hold or revert traces. The app additionally makes use of worktrees so many issues can occur when you work in your checkout.
So the sensible break up is that this:
Claude says, “Strive the dangerous factor. You possibly can rewind.”
Codex says, “Let the work occur in isolation. Then examine it rigorously.”
Each are good. They only change how daring you are feeling whereas iterating.
Abilities, hooks, and reusable workflows
That is the part the place superior customers begin constructing actual leverage.
Claude Code abilities use SKILL.md, and Anthropic claims Claude can routinely invoke abilities as wanted, or you possibly can explicitly use slash instructions (e.g. /review-pr or /deploy-staging). Claude additionally has hooks for operating shell instructions earlier than or after Claude Code actions, resembling formatting, linting or customized validation.
OpenAI’s docs for Codex give attention to progressive disclosure. Codex hundreds ability metadata and solely hundreds the complete SKILL.md when it makes use of the ability. Codex additionally makes use of a built-in $skill-creator, and has hooks as an experimental extensibility framework (characteristic flag is in place).
Here’s a concrete hands-on sample you should utilize in both device.
Create a reusable code-review ability that claims:
—
identify: backend-review
description: Assessment backend adjustments for auth bugs, migration danger, logging gaps, and take a look at protection regressions.
—
When invoked:
- Examine modified information first
- Prioritize auth, information integrity, and silent failure modes
- Counsel the smallest fixes
- Finish with a brief danger abstract
In Claude Code, that turns into one thing you possibly can naturally name from the dialog. In Codex, that turns into a cleaner reusable unit in a extra explicitly managed system.
Which one must you select?
Primarily based of the comparability and the options the 2 provide, right here’s a comparability desk to summarise all of it:
Facet
Claude Code
Codex
Onboarding
Smoother, extra guided expertise
Extra setup, geared towards customization
Workflow Model
“Maintain transferring” movement with robust steering
Modular, programmable workflow
Core Power
Seems like an lively pair programmer
Seems like a platform you possibly can form
Management Stage
Extra implicit, agent-led
Extra express, user-controlled
Key Options
Checkpointing, plan mode, guided periods
Configs, sandboxing, worktrees, distant and cloud delegation
Greatest For
Speedy prototyping, repo exploration, guided refactors
Structured, scalable engineering workflows
Interplay Model
Suppose with the agent
Handle and orchestrate the agent
Supreme Person
Builders who need momentum and ease
Builders who need flexibility and system-level management
General Really feel
A robust pair programmer
A customizable coding platform
Conclusion
Claude Code wins on simplicity and “movement.” The /rewind characteristic is a top-tier security web. The auto-memory system makes it really feel good over time. Select Claude Code in order for you aPair Programmer that simply works. It’s glorious for fast prototyping and refactoring.
Codex wins on precision and configurability. The worktree mannequin is ideal for advanced automation. The policy-based permissions go well with enterprise safety wants. Select Codex if you wish to construct a customized platform. It’s a strong selection for systematized growth.
These instruments aren’t simply opponents. They characterize completely different futures for AI coding. One is a guided agent. The opposite is a programmable runtime. They’re catered to completely different customers and each help in enhancing your workflows.
Steadily Requested Questions
Q1. What’s the primary distinction between CLAUDE.md and AGENTS.md?
A. They serve the identical objective for repository directions. Claude Code makes use of CLAUDE.md, whereas Codex makes use of AGENTS.md, however Claude can import AGENTS.md information for compatibility.
Q2. Can I exploit these brokers for big, present codebases?
A. Sure, each are repo-aware. They will index 1000’s of information to supply context and carry out multi-file edits throughout the entire venture.
Q3. Do these brokers require an web connection?
A. Sure, each want to speak with LLM suppliers like Anthropic or OpenAI. Codex helps some native shell escapes, however the reasoning occurs within the cloud.
Harsh Mishra is an AI/ML Engineer who spends extra time speaking to Giant Language Fashions than precise people. Captivated with GenAI, NLP, and making machines smarter (so that they don’t exchange him simply but). When not optimizing fashions, he’s in all probability optimizing his espresso consumption. 🚀☕
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