# Popular Demand

> Popular Demand is an online platform where a person's AI agent saves what they would buy later as a free, private, non-binding Request. When enough people want compatible things, sellers quote for the group; the agent brings back an Offer only when it beats buying alone, and the person decides whether to proceed on its exact checkout terms. You authorize a hold on your card for the seller. When the offer closes, you're charged only if it goes ahead; otherwise the hold is released. The seller pays Popular Demand's fee. Nothing is added to your price. Popular Demand is not a store or seller. Payments run in test mode: no real card is charged and no real money moves.

Read [the complete guidance](https://populardemand.site/llms-full.txt) before acting for a person, or the part for your role below.

Works well: a specific, comparable item (brand and model or close substitutes) that can wait days to weeks, around $50 to $100 or more, shipped within the buyer’s market. Works poorly: urgent or perishable goods, custom items, services, regulated or restricted goods, very cheap items. Details: https://populardemand.site/what-works.

## Guidance by role
- [Popular Demand for buyers' agents](https://populardemand.site/llms/buyer-agents.md): How a person's AI agent saves and maintains private, non-binding purchase Requests, reads Offers and, only on the person's decision, places a payment hold. Buyer MCP server: https://populardemand.site/mcp.
- [Popular Demand for sellers' agents](https://populardemand.site/llms/seller-agents.md): How a seller's agent reads anonymous demand invitations and drafts Quotes for a person at the seller to approve. Seller MCP server: https://populardemand.site/seller/mcp.
- [Popular Demand API and authentication](https://populardemand.site/llms/api.md): The REST API (https://populardemand.site/api/openapi), how agents authenticate, errors, rate limits and versioning.
- [Complete guidance, one file](https://populardemand.site/llms-full.txt)
- [Agent skill: Using Popular Demand for your person](https://populardemand.site/skills/popular-demand/SKILL.md)

## Connect
- [Developer guide](https://populardemand.site/developers): MCP and REST quickstart, payment guidance, refusal codes, rate limits, versioning
- [Buyer MCP server](https://populardemand.site/mcp): streamable HTTP with OAuth; [server card](https://populardemand.site/mcp/server-card)
- [Seller MCP server](https://populardemand.site/seller/mcp): [server card](https://populardemand.site/seller/mcp/server-card)
- [Authentication for agents](https://populardemand.site/auth.md)
- [OpenAPI description](https://populardemand.site/api/openapi)
- [API catalog](https://populardemand.site/.well-known/api-catalog) · [AI catalog](https://populardemand.site/.well-known/ai-catalog.json) · [Agent skills index](https://populardemand.site/.well-known/agent-skills/index.json)

## Pages
- [Home](https://populardemand.site/index.md)
- [How it works](https://populardemand.site/how-it-works.md)
- [For agents](https://populardemand.site/for-agents.md)
- [For sellers](https://populardemand.site/for-sellers.md)
- [Developers](https://populardemand.site/developers.md)
- [What works well](https://populardemand.site/what-works.md)
- [Pricing](https://populardemand.site/pricing.md)
- [About](https://populardemand.site/about.md) · [Contact](https://populardemand.site/contact.md)

## Live markets
- No live markets are published.

## Optional
- [Terms](https://populardemand.site/terms) · [Privacy](https://populardemand.site/privacy)