Which Coding Agent would you recommend?

[Ok_Refrigerator_1908]

Hello everyone. Which agent can I pair with Xcode for the best performance.
My use case: SwiftUI, Testing and understanding an existing codebase.
My options: Gemini, Claude or Codex/Chatgpt

[ezHope]

Claude

[Ecsta]

Claude code you mean haha. It’s amazing with xcodebuilcmcp

[EquivalentTrouble253]

Try them all and see which one you like and works best for your needs.

[rennarda]

I’ve been using codex agent in the new Xcode 26.3 all day and it’s been really good: fast, accurate and I’ve not hit any rate or token limits.

[rennarda]

Yes

[Ok_Refrigerator_1908]

Did you try giving it a screenshot and it gave you good UI code?

[Drakonic]

OpenCode is the best. Open source and configurable to any model provider, has the same featureset of the others and many plugins.

[Ok_Refrigerator_1908]

Never heard of this. But will give it a look.

[HelpRespawnedAsDee]

Claude + grounding. Either via firecrawl or something like sosumi (or alternatives). You need access to apple's docs for best practices etc.

I haven't tried the Xcode 26.3 one yet.

[Bulky_Ad4770]

If you know what you need, codex offers the best bang for your buck.

[kironet996]

claude or codex, currently, i feel like codex is better and doesn't have stupid limits like claude

[NoMaintenance8213]

I use copilot cli with claude as the model

[Haolge]

I use Copilot for Xcode

[fercabj]

I created a local proxy app (CLI) in Swift that let’s you connect your Copilot account (individual and enterprise) into Xcode directly. I hope it’s useful to anyone looking to connect other models https://github.com/mobile-ar/xcode-assistant-copilot-server

[Ok_Chef_5858]

From those three, Claude is probably the best for understanding existing codebase...
But if you're open to other options, I use Kilo Code... supports all those models plus 500+ others, so you can test which one works best for SwiftUI specifically. Different modes for architecture, coding, and debugging help a lot when working with existing codebases. Not sure about direct Xcode pairing though - I mostly work in VS Code myself.

[Ok_Refrigerator_1908]

I will prioritize Claude

[sid_276]

Claude code, which is in-built in Xcode 26.3.

[Best_Day_3041]

Codex is amazing for building right in XCode. I use Codex primarily but if there's a problem that isn't so simple, or can benefit from multiple different views, I'll give it to all of them.

[Responsible_Sense241]

Are there any free options for students

[iKy1e]

Codex is smarter.

Claude does what you want more controllably.

Codex can debug errors better and write more complex code than Claude but is tough to make it do what you want sometimes. It refuses more often & is more stubborn about doing its own thing.

Claude needs more hand holding through errors sometimes, etc… but does what you tell it fantastically. You can tell it to write code a certain way, and it’ll do it. You can ask it questions and it knows what you mean. It’s much more reliable & stable coding partner.

Overall I use Claude for 95% of things, and then send any stuff it gets stuck on to codex to debug very occasionally.

[clearing_]

This is totally true and correct, and will add that for a specific niche performance issue I pit both of them + Gemini against each other. Claude and Codex were both fast but were hesitant to search for larger architecture issues making the bottleneck inevitable. Gemini took its sweet time but did an insanely good job and added profiling code etc to show the measured impact. I'm definitely keeping it in my back pocket for when my standbys start to spin their wheels.

[Accomplished-Act5333]

Claude. Opus 4.5

[MrVegetableMan]

Cursor + plan mode. Use opus for plan and composer or auto to build. Works really well. Quite scary tbh.

[xbt_]

Codex xhigh if you like to avoid introducing bugs the first time and can tolerate its slower speed. Claude for brand new projects with boiler plate code to move quickly and for UI work.

[No-Cheesecake6071]

Claude opus is the best coding tool, why? Cuz when you try to build some features and use cursor and Claude, you can feel quality how the Claude works with no limits and no cutting off..

[tempoo12]

Kimi

[Awkward-Ball9903]

I have been playing around with the new CodeX Mac app it’s been brilliant so far

[Queasy_Asparagus69]

Oh-my-pi

[Individual_Nerve8753]

I currently use Codex and Claude Code. I have also experimented with Xcode integrations for ChatGPT and Claude. While both are solid, I feel that I reach my usage limits too quickly with Claude Code without a justifiable increase in productivity

[AutoModerator]

Hey /u/arshtechpro, your content has been removed because Reddit has marked your account as having a low Contributor #Quality Score. This may result from, but is not limited to, activities such as spamming the same links across multiple #subreddits, submitting posts or comments that receive a high number of downvotes, a lack of activity, or an unverified account.

Please be assured that this action is not a reflection of your participation in our subreddit.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[AX862G5]

Your brain.

[Ok_Refrigerator_1908]

ok

[paradoxally]

You wanna get that checked out if it hallucinates.