generated: '2026-07-17'
method: searched
source: https://99counties.com/.well-known/ucp
standards:
- id: ucp
  name: Universal Commerce Protocol
  conforms: true
  version: '2026-04-08'
  evidence: /.well-known/ucp advertises dev.ucp.shopping services + capabilities (cart, checkout, fulfillment, discount, order, catalog)
- id: mcp
  name: Model Context Protocol
  conforms: true
  evidence: UCP shopping service exposed over MCP transport at /api/ucp/mcp
- id: oauth2
  conforms: true
  evidence: /.well-known/oauth-authorization-server (RFC 8414) advertises authorization_code + refresh_token grants
- id: oidc
  name: OpenID Connect Discovery
  conforms: true
  evidence: /.well-known/openid-configuration issuer + id_token RS256 + standard claims
- id: rfc7636-pkce
  name: PKCE
  conforms: true
  evidence: code_challenge_methods_supported includes S256
- id: jsonrpc2
  name: JSON-RPC 2.0
  conforms: true
  evidence: MCP endpoint returns JSON-RPC 2.0 request/response envelopes
- id: rfc9457-problem-details
  conforms: false
  evidence: MCP surface uses JSON-RPC error objects, not application/problem+json