Xcode 26 (built-in ChatGPT, free without sign-in)
Apple
Usable by default with no login required; there's a daily free-quota cap, though the vendor hasn't disclosed the exact figure
Xcode 26's Coding Intelligence panel connects to ChatGPT by default — no OpenAI/ChatGPT account registration is required to use it. Once you hit the daily cap, you'll see 'Over daily limit, ChatGPT in Xcode will be unavailable for up to 24 hours'; logging into a paid ChatGPT account or bringing your own third-party API Key raises the quota. Developer community feedback suggests the actual quota is on the tight side, and some users report hitting free-tier limits even while logged into a ChatGPT Plus account (a known bug in account-status recognition).
Fine for occasional code completion or Q&A — heavy use hits the cap quickly. There's a known issue recognizing ChatGPT Plus subscription status, so you may still get rate-limited as if on the free tier even after logging in — try logging out and back in on both macOS and Xcode to troubleshoot.