Script Affinity from VS Code.

In Affinity

1Switch on Affinity's server

In Affinity, open Edit ▸ Settings ▸ Model Context Protocol and enable Enable Affinity MCP. That's the whole server-side setup — Affinity now listens for a client on port 6767. Leave Affinity running and open your favorite photo.

On your Desktop

2Make your project folder

A project is just a folder on your Desktop holding a few small text files — the connection, Claude's briefing, the script. This is the shape you're after:

what you get

affinity-photo-claude-code-windows/
├── .mcp.json          ← the connection — ready to use, don't edit
├── CLAUDE.md          ← Claude's briefing, read at every session start
├── examples/          ← color-boost.js lives here
├── docs/              ← SDK field notes from real sessions
└── verify.ps1         ← connection checker, for when things won't connect

The quickest route is git: clone the companion repo straight onto your Desktop and that exact folder appears — connection file, Color Boost script, Claude's briefing, and a diagnostic tool, all included:

terminal

> cd ~\Desktop
> git clone https://github.com/bolloplayer/affinity-photo-claude-code-windows.git

{
  "mcpServers": {
    "affinity": {
      "type": "sse",
      "url": "http://[::1]:6767/sse"
    }
  }
}

# My Affinity project

- Affinity's MCP server is configured in .mcp.json — never change the URL to localhost.
- Read the Affinity SDK "preamble" doc once per session, before running any script.
- Scripts and exports live in this folder. Start with color-boost.js.

In VS Code

3Open the folder and check the connection

Install VS Code (free) if you don't have it, and add the Claude Code extension: Extensions panel → search Claude Code (publisher Anthropic) → Install. Then, with Affinity already running: File ▸ Open Folder… → pick your project folder → open a Claude Code chat, and approve the affinity server when it asks.

Type /mcp — you should see the affinity server connected, with tools like execute_script and render_spread. That's the whole setup: from here on you just talk.

Prefer a plain terminal? Same thing: cd into the folder, run claude, type /mcp.

Not connecting? The troubleshooting table at the bottom of this page covers the usual causes. (If you cloned the companion repo, it also includes verify.ps1, which checks each link in the chain — Affinity process, port listening, handshake — and tells you which one is broken.)

The payoff

4Run Color Boost

Open a photo in Affinity. In Claude Code, ask:

prompt

> Read the SDK preamble, then run color-boost.js on the
  open document and render the result.

Claude reads Affinity's own SDK documentation over the connection, executes the script, and renders the spread back to itself to confirm it worked. In Affinity you'll see one new adjustment layer appear: Color Boost — a Selective Colour layer that enriches all six colour ranges with classic CMY complement logic while leaving whites, greys, and blacks untouched. It's an ordinary layer: undoable, deletable, yours.

◂▸

Drag the handle to compare. On the right: the Color Boost layer as Affinity shows it.

Iterate

5Make it yours

The layer's opacity is the master strength control. The script defaults to a subtle 25%; the hero image up top is the same layer at 75%. Drag it in Affinity, or just say so: "set the Color Boost layer to 60% and render it." Re-running the script replaces its own layer, so you can iterate without stacking duplicates.

Better yet, chain the whole workflow into one request. This is a real prompt from the session that built this page — and everything after it happened in one go:

Claude re-ran the script at 75%, rendered the spread and judged the result (flagging that the geranium reds were nearing saturation clipping), exported the full-resolution image into IMG/, exported a "before" frame, and composited the labeled before/after JPEG with PowerShell — script, evaluation, files, and folder in a single instruction. That's the part no chat app can follow you into.

And that's the real point. Color Boost is one small script — but the loop you just ran is general. Describe any look — a warm matte film grade, a punchy product-shot cleanup, a batch watermark — and Claude writes the script, applies it, looks at the render, and refines it. Keep the good ones in your repo. They run forever, with or without Claude.