Slimsnap MCP server

SlimSnap connector

Your recent screen captures, as structured data your AI can actually read.

Take a capture in SlimSnap, mark what you mean, then in Claude or Cursor say "look at my last capture". No pasting, no file paths, no clipboard.

What your agent gets

Not a screenshot. A JSON document: every piece of text on screen with its position and colour, plus the arrows, boxes and callouts you drew, and which element each one points at.

That matters for three reasons.

A screenshot pasted into an agent gets downscaled before the model reads it, and nobody tells you. Anthropic's own docs say to pre-resize and crop your images because resizing "might make text less legible". A tall page loses its text entirely.

Images returned over MCP are worse still. In Claude Code they are passed through as text rather than native image blocks, costing roughly 15-25k tokens against about 1.6k for the same image pasted directly, and the model cannot read them at all (claude-code#31208, closed as not planned). A big enough result blows the per-result token ceiling outright (#9152).

And an oversized screenshot can poison a session permanently. It stays in context, gets re-sent every turn, and there is no way to remove it (#55040).

This connector sidesteps all three by never sending the picture. An ordinary screen costs roughly a third less than the same screen as an image, and on a tall page the comparison stops being about cost at all: shrinking an 18,410 pixel page to fit the model's 1568 pixel limit leaves body text 1.4 pixels tall, so the cheap image is cheap because it is unreadable. Either way the agent gets exact coordinates rather than a guess about which button you meant.

When you genuinely need pixels (visual style, spacing, colour balance) there is a separate tool for that, and the image is already downscaled to a size the model can read.

Install

Claude Code

claude mcp add slimsnap -- npx -y @slimsnap/mcp

Then check it: /mcp should list slimsnap with 4 tools.

Claude Desktop

Download slimsnap-mcp.mcpb from Releases and open it. Claude shows an install dialog. The connector then appears under Settings.

Cursor

Or add it by hand to .cursor/mcp.json in your project, or ~/.cursor/mcp.json for every project:

{
  "mcpServers": {
    "slimsnap": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@slimsnap/mcp"]
    }
  }
}

Project config wins over global when both exist. Then ask Cursor about your last capture the same way you would ask Claude.

As a Claude Code plugin (same connector, installed and updated as a plugin)

/plugin marketplace add bickov/slimsnap-mcp
/plugin install slimsnap@slimsnap

You need SlimSnap 0.5.0 or newer, because that is the version that started keeping recent captures on disk.

Approving the tools

The first time Claude Code uses each tool it asks for permission, and the approval is scoped to the folder you were in. Four tools means four prompts, and they come back in the next project. Nothing is wrong; that is how Claude Code gates MCP tools.

To approve them once, everywhere, add this to ~/.claude/settings.json:

{
  "permissions": {
    "allow": [
      "mcp__slimsnap__get_latest_capture",
      "mcp__slimsnap__list_captures",
      "mcp__slimsnap__get_capture",
      "mcp__slimsnap__get_capture_image"
    ]
  }
}

Shortened. The full README is on GitHub.