BuyWhere Singapore Value Intelligence API

{
  "name": "BuyWhere Singapore Value Intelligence API",
  "description": "Semantic product search over Singapore e-commerce with auditable value-scores derived from Shannon entropy across vendor price distributions.",
  "url": "https://useful-data-source-for-agents-production.up.railway.app",
  "version": "1.0.0",
  "documentationUrl": "https://useful-data-source-for-agents-production.up.railway.app/docs",
  "provider": {
    "organization": "nexus-mcp-infra",
    "url": "https://github.com/nexus-mcp-infra/useful-data-source-for-agents-doing-product-price-sdk"
  },
  "capabilities": {
    "streaming": false,
    "pushNotifications": false,
    "stateTransitionHistory": false
  },
  "defaultInputModes": [
    "application/json"
  ],
  "defaultOutputModes": [
    "application/json"
  ],
  "additionalInterfaces": [
    {
      "url": "https://useful-data-source-for-agents-production.up.railway.app/mcp",
      "transport": "MCP"
    }
  ],
  "securitySchemes": {
    "apiKeyHeader": {
      "type": "apiKey",
      "in": "header",
      "name": "X-API-Key"
    },
    "x402Payment": {
      "type": "apiKey",
      "in": "header",
      "name": "X-PAYMENT",
      "description": "x402 payment proof (USDC, Base Sepolia testnet) required on paid operations -- not a classic auth scheme."
    }
  },
  "security": [
    {
      "apiKeyHeader": [],
      "x402Payment": []
    }
  ],
  "skills": [
    {
      "id": "nexus_useful_data_source_for_agents_doing_prod_rank_buywhere_products_by_value_score",
      "name": "Rank BuyWhere Products by Value Score",
      "description": "Searches the BuyWhere Singapore catalogue for products matching a natural-language query and returns them ranked by an auditable value-score derived from Shannon entropy of cross-vendor price variance, causal reliability, and price rank. Do NOT use for real-time stock ticker data, non-SGD markets, or exact product ID lookup. Requires a valid api_key (same as X-API-Key) and an x402 payment.",
      "tags": [
        "product-search",
        "price-comparison",
        "singapore-ecommerce"
      ]
    },
    {
      "id": "nexus_useful_data_source_for_agents_doing_prod_fetch_buywhere_vendor_price_distribution",
      "name": "Fetch Vendor Price Distribution for SKU",
      "description": "Given a BuyWhere product identifier, returns the full cross-vendor price distribution in SGD along with the Shannon entropy of that distribution and the coefficient of variation. Do NOT use as a discovery tool -- requires a known BuyWhere product_id from rank_buywhere_products_by_value_score. Requires a valid api_key (same as X-API-Key) and an x402 payment.",
      "tags": [
        "price-distribution",
        "entropy"
      ]
    }
  ],
  "metadata": {
    "protocol_note": "This service implements the Model Context Protocol (MCP) at /mcp, not A2A's own JSONRPC/gRPC/HTTP+JSON task methods (message/send, tasks/get, etc.). This Agent Card is provided for discovery/indexing purposes; A2A-conformant task orchestration is not implemented."
  }
}