Claude Code + SyncPen: A Workspace Your AI Can Write In

Claude Code is good at producing text — summaries, drafts, documentation, research notes. The catch is that the text lives in your terminal and tends to disappear when the session ends. SyncPen gives it somewhere to stay: a markdown workspace you can read from, write to, and come back to later.

Connecting the two takes a few minutes. Here is how, and why it is worth doing.

What you get

SyncPen is a minimalist, markdown-native writing tool, built for people who like to capture, organize, and connect ideas — researchers, coders, and curious minds. Once you connect it to Claude Code through the SyncPen MCP server, your terminal can:

• search your SyncPen library
• read any document as clean markdown
• list your folders and documents
• create new documents
• update existing ones
• create and rename folders

In short, Claude can use your own notes as context and write its results straight back into your workspace. Nothing to copy and paste in between.

Setup

1. Create an API key

Open SyncPen, go to Settings, then API Keys. Turn on API access and create a key. Copy it right away — you will only see it once. It starts with sp_.

2. Connect Claude Code

One line in your terminal:

claude mcp add syncpen -e SYNCPEN_API_KEY=sp_your_api_key_here -- npx -y syncpen-mcp

If you prefer to keep your configuration in a file, add this to your project .mcp.json or your global ~/.claude.json:

{
  "mcpServers": {
    "syncpen": {
      "command": "npx",
      "args": ["-y", "syncpen-mcp"],
      "env": {
        "SYNCPEN_API_KEY": "sp_your_api_key_here"
      }
    }
  }
}

There is nothing to install. The npx -y syncpen-mcp part fetches and runs the latest package on demand.

3. Check the connection

Run /mcp in Claude Code. You should see syncpen listed, with its tools available. From there, just ask in plain language:

"List my SyncPen folders." "Find my notes about pricing." "Create a document that summarizes what we changed today."

You never name the tools yourself. You describe what you want, and Claude picks the right one.

The tools, in plain terms

Why it is useful

• Your work stays put. Research and drafts do not vanish when you close the terminal. Next week, "read my notes from the kickoff" simply works.
• Research stays close. No switching tabs or hunting through folders. Ask, and the relevant document is in context.
• Draft to published, in one place. Claude writes the first pass; it lands in SyncPen, where you can refine it, work on it with others in real time, and publish to WordPress, Ghost, or Sanity.
• Markdown throughout. Claude thinks in markdown and SyncPen stores markdown, so nothing is lost in translation.
• Your data stays yours. The connection only touches your own account, through a key you control and can revoke at any time.

A short example

Say you owe someone a weekly summary. Try this:

"Read everything in my Reports folder, then create a document called 'Weekly Summary' with the three main themes."

Behind the scenes, Claude lists the documents in the folder, reads each one, and writes a clean summary back into SyncPen. You go from a blank page to a finished, editable document without opening a file. From there, refine a sentence or two and publish.

If something is not working

• Key rejected. Make sure API access is enabled in Settings, and that you copied the whole sp_ key with no trailing spaces. If in doubt, create a new one.
• Tools not showing. Run /mcp to check the connection, then restart Claude Code so it re-reads your configuration. Check that your JSON is valid.
• Organizing into folders. Just ask — Claude can create and rename folders directly, then place documents into the folder you name.

In short

Claude Code writes quickly. SyncPen keeps the writing. Connect them once, and your notes, drafts, and research stay in one place — organized, connected, and ready for you and your AI to pick up where you left off.