Xcode 26.3
Apple (RC xip, downloads, Hacker News):
Xcode 26.3 introduces support for agentic coding, a new way in Xcode for developers to build apps, powered by coding agents from Anthropic and OpenAI. With agentic coding, Xcode can work autonomously toward a developer’s goals — from breaking down tasks to making decisions based on the project architecture, and using built-in tools to get things done.
In addition to Anthropic’s Claude Agent and OpenAI’s Codex integrations, Xcode 26.3 makes its capabilities available through the Model Context Protocol, an open standard that gives developers the flexibility to use any compatible agent or tool with Xcode.
For more information, see Setting up coding intelligence.
The agent sits in Xcode’s sidebar where developers can use it to plan new features, implement them, and review the results. As developers work, the agent generates a transcript of its actions, which lets developers follow along and interact with it. For example, code snippets will appear in the sidebar that can be clicked to take developers directly to the spot in the file where the agent made a change. Code updates can also be simultaneously previewed.
So Xcode just builds entire apps without you now
Xcode’s Codex support will happily trundle away for half an hour sticking its tendrils into every little corner of your project, touching and changing every file. It’s certainly going to be fun to build new projects with, but ain’t no way in hell I want to let that loose on any of my existing apps 😂
Xcode 26.3 getting official Claude and Codex integration without the usual guardrails is interesting enough, but having MCP in the mix is… unusually open for Apple.
[…]
But at least they seem to have done their homework where it regards the in-editor agent harness–not sure how deep they went into IDE primitives (file graph, docs search, project settings), though, and the apparent lack of skills and other creature comforts that all the VS Code–based tools have is a bit of a bummer.
I don’t know if this is super-duper interesting news, but I think it’s super-duper interesting that Apple saw the need to release this now, not at WWDC in June.
They couldn’t even wait for the final version to be shipping before sending out the press release.
I presume Apple announced these integrations now, and not at WWDC, to capture some of the frenzy surrounding tools like Cursor and Copilot.
As a heads-up, it’s around this time of year that Xcode traditionally goes new-OS-only, i.e. requires macOS 26.
They haven’t done that with Xcode 26.3 just yet, but you might find that this is the last point release to run on Sequoia.
AI models can access more of Xcode’s features to work toward a project goal, and Apple worked directly with Anthropic and OpenAI to configure their agents for use in Xcode. Agents can create new files, examine the structure of a project in Xcode, build a project directly and run tests, take image snapshots to double-check work, and access full Apple developer documentation that has been designed for AI agents.
If you’re an developer for Apple’s platforms and were wondering where you rank in their list of priorities consider that they were apparently capable of writing docs and adding meaningful Xcode integrations all this time but they decided to do it to help AI models instead of you.
This repository contains system prompts and documentation from Xcode 26.3, providing insights into Apple’s approach to AI-assisted coding and comprehensive guides for iOS 26 features and frameworks.
Combine is officially dead. Quote from Xcode 26.3 AgentSystemPromptAddition:
Avoid using the Combine framework and instead prefer to use Swift’s async and await versions of APIs instead.
It’s still not officially deprecated, but it’s obviously not preferred for new development.
Previously:
- Codex App
- Apple LLM Generating SwiftUI
- Xcode 26.2
- What Xcode 26’s AI Chat Integration Is Missing
- How to Use Google Gemini in Xcode 26 Beta
- Claude Code Experience
- Swift Assist, Part Deux
- Xcode + Claude
- Tim, Don’t Kill My Vibe
- Whither Swift Assist?
- How to Use Cursor for iOS Development
- Xcode 16 Announced
- LLM Coding Tools in Xcode
