Prompt Studio for Claude Code

An MCP server that lets Claude read and write your Prompt Studio project directly — as text, in your repo, with a version behind every change.

Prompt Studio's document has a text form called Flow. This server makes that text form the interface: Claude reads the grammar, writes Flow, checks it, and folds it into your real project. Anyone with the canvas open watches the screens appear as it goes.

you:     "add a billing journey — plan picker, payment, receipt"
claude:  reads the grammar, writes Flow, checks it, merges it
studio:  three screens and a journey appear on the canvas
git:     prompt-studio.flow updated, ready to commit

Install

As a Claude Code plugin — nothing to install first

/plugin marketplace add faizanahmed-sy-devstree/prompt-studio-mcp
/plugin install prompt-studio@prompt-studio

The server is bundled in the repo, so this needs no npm, no build step and no Node toolchain beyond the one Claude Code already runs on. Then sign in once — the server tells you the exact command for your installation if you ask it to do anything before you have:

node ~/.claude/plugins/cache/*/prompt-studio/*/dist/cli.mjs login

From npm

Not published yet — use the plugin above until it is.

# 1. sign in once, on this machine
npx prompt-studio-mcp login

# 2. register it with Claude Code
claude mcp add prompt-studio -- npx -y prompt-studio-mcp serve

Either way

login asks for your Prompt Studio email and password, exchanges them for tokens, and stores only the tokens in ~/.prompt-studio/credentials.json (owner-readable). Your password is never written to disk, and never goes anywhere near your Claude Code config.

Check it worked — whoami sits next to login, so use whichever of the two paths above you installed with:

npx prompt-studio-mcp whoami          # npm install
node <plugin-dir>/dist/cli.mjs whoami # plugin install

The server acts as you. It reaches exactly the projects your account can reach, and every change is attributed to you in the project's activity feed. There is no service account and no shared credential.

Related MCP server: MCP Prompt Manager

Commands

You never have to use them — asking in plain English reaches the same tools. They exist because nothing in the slash menu otherwise says the server is here.

/prompt-studio:flow is the one worth knowing: it reads the grammar first and checks the source before saving, which is the difference between one write and three failed ones against a live project.

What Claude can do

Keeping a .flow file in your repo

The diagram lives in Prompt Studio, but the text of it can live next to your code, where it can be reviewed in a pull request like anything else:

claude: link this repo to my dispatch project

That writes two files — a .flow file holding the diagram as text, and a small .prompt-studio.json recording which project it belongs to. Commit both.

From then on the file is kept current automatically: any write_flow updates it too, so it never silently becomes the stale copy. sync_status tells you which side has moved, pull_flow brings the studio's version down, and push_flow sends yours up.

Four things it does deliberately

Merge is the default. Asked to add a billing journey, a model writes the billing journey — not the other eleven. A write that replaced the document would delete the rest of the project every single time. replace exists, is named plainly, and has to be asked for.

Every write snapshots first. The version is taken before the change and labelled with what the change was about, so the history is a list of states you can return to rather than a list of times something happened. restore_version also snapshots before restoring, so undoing is itself undoable.

Stale writes are refused, not merged. A write sends the version it read as its base. If somebody saved in between, it comes back as a conflict telling Claude to read again and reapply. It never lands on top of your colleague's work. push_flow does the same for the file on disk.

Checking is free. check_flow needs no project and touches nothing, so getting the grammar right costs iterations rather than writes.

Configuration

Stored tokens win over environment variables: somebody who ran login meant it, and silently preferring a stale env var over that is an hour of confusion.

Running against a local backend:

PROMPT_STUDIO_API_URL=http://localhost:8010 npx prompt-studio-mcp login

Building it yourself

pnpm install
pnpm build          # bundles dist/cli.mjs and dist/server.mjs
pnpm test           # unit tests, no network
pnpm typecheck

End to end, against a running backend — this one creates a real account and a real project:

PROMPT_STUDIO_API_URL=http://localhost:8010 node tests/e2e.mjs

The vendored studio

src/studio/ is a copy of the slice of Prompt Studio this server needs: the Flow parser, the serializer, the merge rules and the prompt engine. It is vendored rather than imported so that installing this package does not require checking out the app — which is the entire point of shipping it separately.

To refresh it against a local checkout:

pnpm sync           # defaults to ../prompt-studio
git diff            # this is the review

The sync script walks the real import graph from a handful of entry points, so it copies exactly what is reachable and nothing else. It refuses to vendor React components — one appearing means a barrel file is being imported where a direct module should be.

Licence

MIT.