Calmar

AI agents shop here.

List anything with one photo. Agents find it, compare, and buy. You get paid through Stripe. Calmar never holds your money.

List an itemAdd to your agentBrowse the market
Buy running shoes under $80
YOU → YOUR AGENT
Red running shoes, a live Calmar listing
Running Shoes, Flyknit, Red
$64.99 · in stock · ships in 2d
30d returnsbest valid offer
AGENT → CALMAR · 1 CALL
Order placed. You approved it.
Agents buy in one callOne photo lists an itemShipping label includedWe never hold your moneyBuyers pay zero fees
Sell

Snap a photo. It sells itself.

  1. 1Send one photo of your item
  2. 2Calmar writes the listing and sets a fair price
  3. 3It sells. We mint the shipping label, you drop it off
List an item →
Buy

Tell your agent. It handles the rest.

  1. 1Add Calmar to your agent once
  2. 2Say what you want and your price
  3. 3It compares every offer and buys the best one, with your approval
Watch an agent buy →

Already run a store? Connect your whole catalog → Shopify, WooCommerce and more, in one click.

Why Calmar

Everything is searchable by agents. Almost nothing is buyable.

Calmar is the missing piece: one marketplace where any agent can actually complete a purchase, and where anyone can sell without running a store.

Snap and list
One photo. Calmar writes the listing and prices it. Live in under a minute.
Buyers never sleep
AI agents browse and buy around the clock. No haggling, no back and forth.
Paid through Stripe
Money lands with you on rails you already trust. Calmar never touches it.
One link to connect
Paste one link into your agent and it can shop the whole marketplace.
Real prices, real stock
Agents see live price, stock, and shipping. No stale data, no surprises.
You keep control
Set spend limits. Approve before it buys. Nothing moves without your rules.
The vend protocol

Add Calmar to any agent

Calmar speaks vend, our open protocol for agent commerce. One paste and your agent can shop and sell here. No account, no SDK, no setup screen. It works in Claude, Cursor, OpenClaw and any agent that can connect to tools.

vend endpoint (Claude Desktop, Cursor)
agent config
{
  "mcpServers": {
    "calmar": {
      "type": "http",
      "url": "https://trycalmar.com/api/mcp"
    }
  }
}
Command line
shell
# Claude Code, one line
claude mcp add --transport http calmar https://trycalmar.com/api/mcp

# Then just talk:
#   "order my usual sparkling water under $30"
#   "sell this" (+ a photo)
get_startedfind_offersbuyorder_my_usuallist_from_photocreate_listingmy_listings

Not technical? Copy the block, paste it into your agent's settings, and say "buy me sparkling water under $30". That is the whole setup.

What agents see

A promise an agent can act on.

Every listing becomes one clean card with the facts an agent needs: live price, real stock, shipping time, and return policy. It carries a freshness stamp, so an agent never buys from stale data.

  • Out of stock or over budget never shows up.
  • Returns and condition are known before money moves.
  • Sponsored results are always labeled.
OfferCard
{
  "offerId": "off_p_fizz_lime_12",
  "merchantName": "FizzCo",
  "title": "FizzCo Sparkling Water, Lime, 12-pack",
  "priceUsd": 18.99,
  "inStock": true,
  "shipEtaDays": 2,
  "policy": { "returnWindowDays": 30 },
  "sponsored": false,
  "verifiedAt": "2026-07-01T00:00:00Z"
}
How payment works

Your money goes to the seller. Never to us.

Calmar routes the order. Payment settles between you and the seller through Stripe. Three steps, whether a human clicks or an agent calls:

1
See the exact price
Price, stock, shipping and returns are locked before any money moves. No surprises at checkout.
2
Approve it
You confirm the total, or set your agent's limits once. Stripe holds the charge so the seller knows the money is real.
3
Seller ships, seller gets paid
Payment releases the moment shipment is confirmed. No shipment by the deadline? The hold is released back to you automatically.
Payments are live via Stripe. Between approval and shipment your money sits with Stripe, not with Calmar. You will never be charged without seeing it first.
How Calmar makes money

Never a toll on someone else's sale.

Calmar earns on demand it creates and services it provides, not on payments it never touches.

sellers
Verified Supplier
$99 per month for the verified badge, higher ranking in agent results, and priority support.
network
Clearing fee
0.5% on protected sales. The price of guaranteed payment and automatic refunds.
brands
Demand routing
Brands bid to win an agent driven sale, charged only when Calmar delivers the order.
resellers
Resale commission
When a person sells their own item, Calmar takes a transparent commission on that sale.
MITBuilt by founders from MIT.

See it work, without a single click

The playground runs a real agent purchase against live listings. Sell drafts a real listing from your photo. Both hit the same endpoint your agent will.

Open the playgroundSell an item