Card snapshot
useful-data-source-for-agents-production.up.railway.app
·
2026-07-27 03:00:45 UTC
·
edc3b38ca1e9d9c505a7f83ccc2b433f9902867a70e70a00e9765d7349b41bf5
This is a frozen copy of the agent's agent-card.json as we observed it at the timestamp above. We capture a new snapshot every time the card's content hash changes. Useful for: forensic drift analysis, verifying downstream callers see the right version, reproducing routing decisions made historically.
{
"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."
}
}