Watchpost for Claude Desktop

A safety net for the things Claude wants to buy.

Claude Desktop is the most direct way to give Claude a credit card. Watchpost sits between Claude and the merchant, runs three checks per purchase, and either lets it through, asks you, or blocks it. Claude itself doesn't know it's being checked. The integration is the standard Model Context Protocol; nothing custom on Anthropic's side.

Get WatchpostHow it works
One command
npx @watchpost/mcp install
The CLI opens a browser to confirm your account, writes the connection token into Claude Desktop's claude_desktop_config.json, and asks you to restart the app. You're done in under five minutes.
Real verdicts

What it looks like with Claude Desktop.

Approved14:02
amazon.comUSB-C cable, 6ft, braided
$15.99

Trusted merchant, listing is clean, well within your daily cap. Claude proceeds without asking you.

Review14:02
open-ai-credits.exampleAPI credits — $50, auto-renew
$50.00

Listing has recurring-billing language but Claude marked it one-off. You get a push to confirm.

Blocked13:58
too-good-deals.ioPremium subscription, best deal
$199.00

Trust score below your minimum and the listing has hidden Unicode pointed at the AI. Watchpost stops it without bothering you.

Setup with Claude Desktop

Five minutes, no surprises.

  1. 01
    Sign up

    Email and a password. No credit card to start. You'll land on a dashboard with sensible defaults already set.

  2. 02
    Set your rules

    Caps per purchase, day, and month. An ask-me threshold for anything above your usual range. Categories you don't buy.

  3. 03
    Run the installer

    On your Mac, Windows, or Linux machine: npx @watchpost/mcp install. The CLI confirms your account in the browser, writes the MCP entry into Claude Desktop's config, and asks you to restart Claude.

  4. 04
    Ask Claude to buy something

    From your usual Claude conversation, ask Claude to buy something. Watchpost intercepts the request, runs the checks, and Claude either proceeds, waits for your tap, or tells you it can't.

Frequently asked

Specific to Claude Desktop.

Does Claude have to be on a paid Anthropic plan?
No. Watchpost works with any Claude Desktop install, free or paid. The connection uses the open Model Context Protocol, which Claude Desktop supports out of the box.
What if Claude is using a tool like a browser or Stripe Link to actually pay?
Watchpost runs before the payment step. As long as Claude calls watchpost_check_purchase before it executes the payment tool, you're protected. The MCP install guides Claude to use Watchpost first.
Can I see what Claude tried to buy before I noticed the push?
Yes. The dashboard at watchpost.systems/transactions lists every verdict, with reasoning and outcome. Search by merchant, filter by decision, drill into any one.
What happens to the listing data Claude sends Watchpost?
We send the listing text to Anthropic's API for the manipulation scan, then forget it once the verdict is issued. Anthropic does not retain or train on API content under their default API terms.

Switch it on for Claude Desktop.

Free for 25 verdicts a month. Upgrade only when your agent gets busy.

Get WatchpostSee pricing