Floorplan: a plain-English map of the app you built

Floorplan has Claude read an app you built and draw it as a map you can zoom into, so "what happens at checkout?" gets a picture for an answer. Each card carries a human name and a one-line description, "Takes card payments at checkout" in place of "Stripe API wrapper", with the real path underneath in small type. Hayden Smith (GitHub user haydenschmitty) publishes it as a plugin for Claude Code and Codex under the MIT license. Anthropic doesn't publish it. If plugins and skills are new to you, read Claude Code skills first.

What a first run does

Scripts in plain Node do the mechanical half. They find every git repo under the folder, parse imports and routes, and match each web request in the frontend to the endpoint that answers it, across separate repos too. Then Claude writes the parts list: the SKILL.md aims for 3 to 9 top-level nodes, a description for every file and route, and splits that writing across parallel subagents once a codebase passes about 150 files.

Code in TypeScript, JavaScript, Python, Go, Rust, Java, Kotlin and Scala is parsed, and endpoints are found for Express, FastAPI, Django, Next.js and Spring, among others. The output is floorplan/index.html, opened through a small server on 127.0.0.1.

On the map

• Health check. Keys left in the code or exposed through NEXT_PUBLIC_ and VITE_ variables, Supabase tables without row-level security, open Firebase rules, Stripe webhooks that skip the signature check, endpoints with no sign-in. Each item has a ready-to-paste fix prompt. The SKILL.md itself calls it a quick automatic check, and it's no substitute for a security audit.
• Recent work. Cards Claude just changed turn green, each with a note tying the edit to what you asked for.
• Ask bar. "If I change the users table, what breaks?" returns an answer and a mini-map of the pieces involved. In Claude Code it runs claude -p on your own sign-in, read-only.
• Blueprints. Share a PRD before any code exists and you get the planned system as dashed cards, plus the decisions it leaves open.

How to install it

You need Node.js 18 or newer. In the CLI, or the desktop app's Code tab:

claude plugin marketplace add haydenschmitty/floorplan
claude plugin install floorplan@floorplan

Start a new session after that. For Codex the pair is codex plugin marketplace add haydenschmitty/floorplan and codex plugin add floorplan@floorplan. Install the Claude Code CLI even if you use the desktop app: the Ask bar reads your code through it.

Example request

Make me a floorplan of this app. The frontend is in [folder] and the backend in [folder]. List every high-severity Health item, then add a flow showing what happens when a user [action, e.g. places an order].

Later, "Update the floorplan" re-reads only what changed. The command is /floorplan:floorplan, or $floorplan in Codex.

Limits

• The first map is the expensive one. Every file and endpoint gets described, so a big app takes longer and uses more of your Claude or ChatGPT plan. Updates re-read only what changed.
• One opt-in network request. After a map has been open for two minutes, a card offers an email when Floorplan Cloud launches. Nothing leaves your machine unless you click Notify me, and the address then lands in a private Google Sheet the author keeps.
• Files it adds. A floorplan/ folder that ignores itself in git. If you say yes, it also writes a block into CLAUDE.local.md so later sessions start from the map.
• Local only. The server accepts connections from your own computer alone. On a remote box, run node floorplan/serve.mjs on your machine instead.

When to use it

It fits an owner who wants to see where an AI-built app is exposed, or a team onboarding someone onto a product split across repos. For studying a large codebase function by function, Understand Anything builds a developer's knowledge graph instead.