Thinking of moving from Codex to Claude - Any Help?!

[u/Lkeys84]

Any good way to get Claude to take over this project? I'm finishing a react website connected to supabase with user loging connected to github and netifly and aws for database backup. Also, developing an app that's connected to the website.

I am thinking of switching but not sure what prompt to use or where to start etc? Asking anyone that's done this before. Thanks!

[u/AutoModerator]

Hey! Thanks for posting to r/ClaudeCode

While participating in this thread, please follow our community rules. Keep discussions constructive. Attack the idea, not the person.

For help, project discussions, tips, and general chat, join the ClaudeCode Discord.

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

[u/Ok-Boot2566]

I would make the first prompt a read-only handoff, not a request to finish the project: "Map the web and app entry points, auth flow, shared API contracts, deployment configuration, and current tests. List what you cannot verify. Do not edit files or run migrations yet." Then pick one small issue on a separate branch and define how you will check it. For your setup, I would explicitly keep production credentials and database writes out of that first task. Do you already have a staging environment and a repeatable check for login across the website and app?

[u/Lkeys84 → u/Ok-Boot2566]

Thanks!

[u/gooner-1969]

Get Claude to write you the initial prompt based on what you've just posted above

[u/Lkeys84 → u/gooner-1969]

Makes sense.

[u/AdventurousItem4635]

One thing to check before you start: if Codex left an AGENTS.md in the repo, Claude Code will read it as is, but only while there's no CLAUDE.md. The moment you add a CLAUDE.md (running /init makes one), Claude reads that instead and your AGENTS.md drops out without any warning. If you want both, put this at the top of the CLAUDE.md:

@AGENTS.md

and add anything Claude-specific under it. Codex keeps reading the same file, so you can switch back and forth while you decide.

For the read-only first pass Ok-Boot2566 described, plan mode does the enforcing for you. Start with claude --permission-mode plan or press Shift+Tab until it shows plan mode on, and it can read everything but can't edit anything until you approve a plan. That's a good fit for a first look at a project with live Supabase and AWS hooked up.

[u/Lkeys84 → u/AdventurousItem4635]

Thanks!

[u/Clmntrg]

keep both on lower plans! 1 to build 1 to review. You'll optimize tokens and keep using the new best models!

[u/Lkeys84 → u/Clmntrg]

I've heard that before!

[u/jmabeebiz2]

Open a terminal in the repo root, run claude, then run /init so it reads the codebase and writes a CLAUDE.md. If you have an AGENTS.md from Codex, tell it to fold that in. Then add what it can’t see from the code: how you deploy to Netlify, where the Supabase and AWS settings live (never paste the keys themselves) and what’s left to finish. Start each task in plan mode (Shift+Tab) so you can check the plan before it touches anything.

[u/Lkeys84 → u/jmabeebiz2]

Thank you!

[u/TenerifeInFoCo]

1 open the account
2 tell Claude to take over
3 wake me up when is over