Paste It MCP

Local Model Context Protocol server for agents. Off by default — enable from the menu bar MCP checkbox after opening Paste It normally.

• MCP URL: http://127.0.0.1:17321/mcp
• Transport: Stateless HTTP only (POST /mcp)
• Bind: loopback only (127.0.0.1)
• Mutating the main timeline / capture / settings is not exposed

Configure clients with this HTTP MCP URL (not a command/args spawn). Paste It must already be running.

Prerequisites

1. Open Paste It (double-click the app as usual)
2. Right-click the menu bar icon → enable MCP (copies the URL automatically)
3. Or use Copy MCP URL while MCP is on

Client config (example)

Point your MCP client at:

http://127.0.0.1:17321/mcp

Requests must be JSON-RPC over HTTP with:

• Content-Type: application/json
• Accept: application/json

Tools

Tool	Purpose
paste_it_health	clipCount + running
paste_it_list_clips	limit / offset / type / sourceApp
paste_it_get_clip	id + optional includeBlobs
paste_it_search	q / limit / … (same query language as the app)
paste_it_render_screenshot	Ephemeral cards + real TimelineView → screen-region PNG path

paste_it_render_screenshot

Builds a throwaway history (does not write main history), shows a temporary glass panel using the same TimelineView toolbar and cards as the product, captures a screen-region PNG (so Liquid Glass composites correctly), then destroys the session.

Default output directory:

~/Library/Application Support/PasteIt/AgentScreenshots/

Arguments:

{
  "cards": [
    {
      "type": "text",
      "title": "Snippet",
      "plainText": "let x = 1",
      "sourceAppName": "Xcode",
      "sourceBundleIdentifier": "com.apple.dt.Xcode"
    },
    {
      "type": "link",
      "plainText": "https://example.com",
      "linkTitle": "Example",
      "sourceAppName": "Safari",
      "sourceBundleIdentifier": "com.apple.Safari"
    }
  ],
  "ui": { "query": "", "selectedIndex": 0 },
  "outputPath": null
}

Result (JSON text content):

{ "path": "/Users/…/AgentScreenshots/render-….png", "width": 1120, "height": 320 }

Card fields (all optional except enough content to render):

Field	Notes
type	text, url (or link), image, file, …
plainText, title, htmlText	Text content
sourceAppName, sourceBundleIdentifier	Source chrome
ocrText, linkTitle, fileURLString	Extra metadata
imageBase64 / imagePath	Image cards (imagePath max 25MB; loaded off the UI thread)
linkImageBase64	Optional link preview image (skips network fetch when provided)

For type: link/url without linkImageBase64, render waits for OG image / favicon fetch before capturing. Concurrent renders return a tool error while one is in progress. If the listener ever dies, toggle MCP off/on to rebind :17321.

Manual smoke test

# initialize
curl -s http://127.0.0.1:17321/mcp \
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-11-25","capabilities":{},"clientInfo":{"name":"curl","version":"0"}}}'

# tools/list
curl -s http://127.0.0.1:17321/mcp \
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json' \
  -d '{"jsonrpc":"2.0","id":2,"method":"tools/list","params":{}}'

# tools/call health
curl -s http://127.0.0.1:17321/mcp \
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json' \
  -d '{"jsonrpc":"2.0","id":3,"method":"tools/call","params":{"name":"paste_it_health","arguments":{}}}'

Old REST paths (/v1/*) are not served (404).