ModRetro

ModRetro Agent Commerce API (UCP over MCP)

ModRetro's agent-facing commerce API. A remote Model Context Protocol server implementing the Universal Commerce Protocol shopping service (versions 2026-04-08 and 2026-01-23), exposing 13 tools across catalog search and lookup, cart, checkout and order. initialize and tools/list answer anonymously; every tools/call requires a fetchable UCP agent-profile URI, and the order and checkout tools additionally require a Shopify agent JWT. complete_checkout requires an idempotency key and, per ModRetro's own robots.txt and /agents.md, explicit contemporaneous human approval of payment.

GitHub

Documentation

📖
Documentation
https://modretro.com/agents.md
📖
Authentication
https://raw.githubusercontent.com/api-evangelist/modretro/refs/heads/main/authentication/modretro-authentication.yml
📖
RateLimits
https://raw.githubusercontent.com/api-evangelist/modretro/refs/heads/main/rate-limits/modretro-rate-limits.yml

Other Resources

🔗
MCPServer
https://raw.githubusercontent.com/api-evangelist/modretro/refs/heads/main/mcp/modretro-mcp.yml
🔗
OAuthScopes
https://raw.githubusercontent.com/api-evangelist/modretro/refs/heads/main/scopes/modretro-scopes.yml
🔗
ErrorCatalog
https://raw.githubusercontent.com/api-evangelist/modretro/refs/heads/main/errors/modretro-problem-types.yml
🔗
DataModel
https://raw.githubusercontent.com/api-evangelist/modretro/refs/heads/main/data-model/modretro-data-model.yml
🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/modretro/refs/heads/main/apis.yml

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API entry from apis.yml

apis.yml Raw ↑ 
name: ModRetro Agent Commerce API (UCP over MCP)
description: ModRetro's agent-facing commerce API. A remote Model Context Protocol server implementing
  the Universal Commerce Protocol shopping service (versions 2026-04-08 and 2026-01-23), exposing 13 tools
  across catalog search and lookup, cart, checkout and order. initialize and tools/list answer anonymously;
  every tools/call requires a fetchable UCP agent-profile URI, and the order and checkout tools additionally
  require a Shopify agent JWT. complete_checkout requires an idempotency key and, per ModRetro's own robots.txt
  and /agents.md, explicit contemporaneous human approval of payment.
humanURL: https://modretro.com/agents.md
baseURL: https://modretro.com/api/ucp/mcp
tags:
- Agentic Commerce
- MCP
- Universal Commerce Protocol
- E-Commerce
- Catalog
- Checkout
tags_raw:
- Agentic Commerce
- Model Context Protocol
- Universal Commerce Protocol
- E-Commerce
- Catalog
- Checkout
properties:
- type: MCPServer
  url: mcp/modretro-mcp.yml
- type: Documentation
  url: https://modretro.com/agents.md
- type: Authentication
  url: authentication/modretro-authentication.yml
- type: OAuthScopes
  url: scopes/modretro-scopes.yml
- type: RateLimits
  url: rate-limits/modretro-rate-limits.yml
- type: ErrorCatalog
  url: errors/modretro-problem-types.yml
- type: DataModel
  url: data-model/modretro-data-model.yml