NorthCinder hit 1,197 stars in three days for a shopping-agent MCP where seller payment can't buy rank.

It ranks products against a buyer's brief and structurally excludes affiliate and sponsorship data from ranking inputs, keeping labeled sponsored offers below every organic result. Checkout requires a separate signed, single-use mandate binding the exact offer, quantity and spending cap, and the client reruns the deterministic ranking over service-disclosed inputs so the buyer can verify independently. (GitHub) 399 stars a day, the fastest climb in today's set. The design directly answers the open question of who pays for agent commerce, and the answer is "not by moving the ranking."