Your AI asks. You sign.

When a document needs your signature, a window opens on your Mac. You see the document, sign it, and your AI agent gets the signed PDF.

Download directly

Free · no account, no tracking · macOS 14 or later · checked by Apple · updates itself · direct download is version 1.0.10

An AI assistant chat asking for a signature, next to the Signature MCP window with a signature drawn on the pad.

Nothing is signed without you

Every request opens a window that names the AI app, says what it's for and shows the document. You draw the signature and click Sign.

Sign on the document

Scroll through the PDF, pinch to zoom, and drag your signature to where it belongs. Signature MCP writes it into the file.

For your company

Add your name, role and company stamp once. They go with the signature when your AI asks and you agree.

Disposable by design

A signature is drawn fresh for every request. The files your AI receives are deleted after ten minutes.

Works with any AI agent

Signature MCP is an MCP server in your menu bar. Copy the setup prompt, paste it into your agent, and it connects itself.

Private

The server only listens on your Mac. No account, no tracking. Signature MCP collects no data.

See it in 44 seconds

Watch on YouTube

The Signature MCP window with a contract page on the left, the signature placed on its signing line, and the signature pad on the right.

Set up in a minute

Download and open. Move Signature MCP to Applications and open it. It lives in the menu bar and has no Dock icon.
Connect your AI. Under Connect Your AI, click Copy Setup Prompt and paste it into your agent. It adds Signature MCP to its own settings.
Ask for a signature. Tell your agent to have a document signed, for example “sign the contract in my Downloads folder”.

Or add it by hand. Signature MCP is a local MCP server (Model Context Protocol) that AI apps start as a command; it needs no token and no account. The path has no space in it, so it also works in apps that take the command as one line. (A copy installed before version 1.0.7 may still be named differently: Manual Setup in the panel has the commands with its path.)

Claude Code

claude mcp add --scope user signature-mcp -- '/Applications/SignatureMCP.app/Contents/MacOS/SignatureMCP' --stdio

Codex CLI

codex mcp add signature-mcp -- '/Applications/SignatureMCP.app/Contents/MacOS/SignatureMCP' --stdio

Claude Desktop, Cursor, Windsurf, Gemini CLI and other apps with an `mcpServers` config

{
  "mcpServers": {
    "signature-mcp": {
      "command": "/Applications/SignatureMCP.app/Contents/MacOS/SignatureMCP",
      "args": [
        "--stdio"
      ]
    }
  }
}

What your agent can do

Signature MCP gives your agent ten tools. Every one that signs or changes something opens a window for you to confirm.

sign_document Shows a PDF or image; the user signs on the page and the agent gets the signed PDF.
sign_documents Several files in one window: one signature, a signed PDF for each.
request_signature Asks for a signature alone and returns it as a PNG with a transparent background.
request_stamp Asks for the company stamp alone.
get_company_profile Reads the app version, the company text, whether a stamp is set, and the inbox folder.
set_company_text Proposes the lines under a company signature; the user confirms.
set_company_stamp Proposes an image as the company stamp; the user confirms.
remove_company_stamp Removes the company stamp; the user confirms.
discard_signatures Deletes the signature files the agent received, once it has used them.
close_app Quits Signature MCP when you say you're done; it starts again by itself the next time it's needed.

Questions

What is Signature MCP?

Signature MCP is a free menu bar app for the Mac and a local MCP server (Model Context Protocol). It lets an AI agent ask you for a handwritten signature: a window opens, you sign, and the agent gets the signed PDF or the signature as an image.

Can my AI sign something without me?

No. Every request opens a window on your Mac. You draw the signature each time and click Sign. Nothing is stored for reuse, and if you cancel, your AI is told you didn't sign.

Which AI apps work with Signature MCP?

Any app that supports MCP servers and runs on the same Mac, such as Claude Code, Claude Desktop, Codex CLI, Cursor, VS Code, Windsurf and Gemini CLI.

What happens to my signature?

It's turned into an image, or written into the PDF, and handed to your AI app as a temporary file. The file is deleted after ten minutes, when your AI says it's done, and when you quit Signature MCP.

Is the signature legally valid?

A signature drawn in Signature MCP is a simple electronic signature, which is accepted for many everyday documents. Some documents need a handwritten or a qualified electronic signature instead. Check what your document requires.

What does it cost?

Signature MCP is free. There is no account and no subscription.

How is it updated?

The version you download from signaturemcp.app updates itself: it looks for a new version once a day and installs it after one click. The Mac App Store version is updated by the App Store.

Can other devices on my network reach it?

No. Signature MCP only accepts connections from your own Mac: its server listens on 127.0.0.1, which other computers, phones or AI agents on your network can't reach. Programs running on your Mac can send it requests, but nothing is signed and nothing about your company text or stamp changes without you confirming it in a window.

More answers and troubleshooting on the support page.

What you need

A Mac with macOS 14 or later
An AI app that supports MCP servers

Good to know

A signature drawn in Signature MCP is a simple electronic signature. Some documents need a handwritten or a qualified electronic signature instead, and a company stamp has no legal force of its own. Signature MCP doesn't check who signs and gives no legal advice.

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