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io.github.nexus-mcp-infra/useful-data-source-for-agents-doing-product-price-sdk

REMOTE · USEFUL-DATA-SOURCE-FOR-AGENTS-PRODUCTION.UP.RAILWAY.APP · SCANNED AUG 3

Semantic product search over Singapore e-commerce, ranked by an auditable entropy-based value-score

+4 this week 64 Trust /100

Deprecated

This server is marked deprecated in the MCP registry.

Trust breakdown (6 categories)

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score →

Endpoint Security57
Transport & Reachability100
Schema Quality & AI Usability61
  • AI-judged instruction clarity (good).Pass
  • Context-footprint check failed: tool/resource definitions use about 477 tokens (~238/item across 2 items; 2 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
  • Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management27
  • Stability observed for 8 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
  • 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
  • 100% of tool parameters carry a description.Pass
  • Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Capabilities100
  • Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
Install

Add this component to your MCP client. Where a client-specific snippet is available, pick your client below and copy it straight into your config; otherwise use the connection detail shown.

remote · useful-data-source-for-agents-production.up.railway.app

# add to Claude Code
claude mcp add --transport http nexus-mcp-infra-useful-data-source-for-agents-do https://useful-data-source-for-agents-production.up.railway.app/mcp
# ~/.codex/config.toml
[mcp_servers.nexus-mcp-infra-useful-data-source-for-agents-do]
url = "https://useful-data-source-for-agents-production.up.railway.app/mcp"
// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "nexus-mcp-infra-useful-data-source-for-agents-do": {
      "type": "remote",
      "url": "https://useful-data-source-for-agents-production.up.railway.app/mcp",
      "enabled": true
    }
  }
}
# add to OpenClaw
openclaw mcp add nexus-mcp-infra-useful-data-source-for-agents-do --url https://useful-data-source-for-agents-production.up.railway.app/mcp --transport streamable-http
# ~/.hermes/config.yaml
mcp_servers:
  nexus-mcp-infra-useful-data-source-for-agents-do:
    url: "https://useful-data-source-for-agents-production.up.railway.app/mcp"
// mcp.json
{
  "mcpServers": {
    "nexus-mcp-infra-useful-data-source-for-agents-do": {
      "type": "http",
      "url": "https://useful-data-source-for-agents-production.up.railway.app/mcp"
    }
  }
}

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

Changelog

Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.

  • 3 Aug 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 at this one. The score rises as the window fills, whether or not the server changes.

  • 31 Jul 26 +1
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 30 Jul 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 29 Jul 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 7 to 10. That category is still filling its 30-day observation window: 2 days of observed history at the previous scan, 3 at this one. The score rises as the window fills, whether or not the server changes.

  • 28 Jul 26 +1
    • Tool “nexus_useful_data_source_for_agents_doing_prod_fetch_buywhere_vendor_price_distribution” now declares an output schema functional
    • Tool “nexus_useful_data_source_for_agents_doing_prod_rank_buywhere_products_by_value_score” now declares an output schema functional
    • First check of Tool coverage: 100 functional
  • 27 Jul 26 0
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 26 Jul 26 60

    First indexed and scored.

Diagnostics

Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.

Captured 3 Aug 2026 · Probed https://useful-data-source-for-agents-production.up.railway.app/mcp

TLS valid

Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .

Subject Issuer Valid from Valid until Key Signature Serial
CN=*.up.railway.app CN=YE1,O=Let's Encrypt,C=US 29 Jul 2026 27 Oct 2026 ECDSA 256 ECDSA-SHA384 6da79bb561da3efeb0e751ca21abd3999fe
SANs: *.up.railway.app, up.railway.app
CN=YE1,O=Let's Encrypt,C=US (CA) CN=Root YE,O=ISRG,C=US 3 Sept 2025 2 Sept 2028 ECDSA 384 ECDSA-SHA384 5ddd70dd31f801c85c186a7a04b80afe
CN=Root YE,O=ISRG,C=US (CA) CN=ISRG Root X2,O=Internet Security Research Group,C=US 13 May 2026 2 Sept 2032 ECDSA 384 ECDSA-SHA384 872165fc34b6e5fba8add5b3705fb53a
CN=ISRG Root X2,O=Internet Security Research Group,C=US (CA) CN=ISRG Root X1,O=Internet Security Research Group,C=US 13 May 2026 2 Sept 2032 ECDSA 384 SHA256-RSA 6c8f1dc727c7117f7baf853ac980f9cd
DNSSEC insecure

Validation of useful-data-source-for-agents-production.up.railway.app. Not signed

Zone DS Keys Algorithms Outcome
. trust_anchor 20326, 38696 8, 8 Verified
app. present 23684 8 Verified
railway.app. absent Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation
Authentication No authorisation required

The endpoint answered without asking for a token. Anyone who knows the URL can reach it.

Result No authorisation required
HTTP status 200
Transports 2 probes
Transport URL Outcome Status Location
streamable-http https://useful-data-source-for-agents-production.up.railway.app/mcp Verified 200
http (plaintext) http://useful-data-source-for-agents-production.up.railway.app/mcp HTTPS enforced 301 https://useful-data-source-for-agents-production.up.railway.app/mcp
MCP tools — 2 exposed · ~477 tokens

The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability.

Tool Tokens
nexus_useful_data_source_for_agents_doing_prod_fetch_buywhere_vendor_price_distribution ~196

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. Use this when an agent already knows the product and needs to audit price fairness or detect outlier vendor pricing. Do NOT use as a discovery tool — it 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.

NameTypeReqDescription
api_keystringyesAPI key required for this paid operation -- same secret configured as X-API-Key on the REST endpoints (BUYWHERE_API_KEYS). Payment (x402) alone is not sufficient; both gates must pass.
product_idstringyesBuyWhere internal product identifier as returned by rank_buywhere_products_by_value_score. Format: alphanumeric string.

Structured output declared, but exposes no named fields.

No examples provided.

nexus_useful_data_source_for_agents_doing_prod_rank_buywhere_products_by_value_score ~281

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. Use this when an agent needs ranked product recommendations for a Singapore market query with auditable justification per product. Do NOT use for real-time stock ticker data, non-SGD markets, or exact product ID lookup (use fetch_buywhere_vendor_price_distribution for that). Requires a valid api_key (same as X-API-Key) and an x402 payment.

NameTypeReqDescription
api_keystringyesAPI key required for this paid operation -- same secret configured as X-API-Key on the REST endpoints (BUYWHERE_API_KEYS). Payment (x402) alone is not sufficient; both gates must pass.
limitnumberMaximum number of ranked products to return. Higher values increase latency. Recommended 5-20 for agent consumption.
min_value_scorenumberMinimum composite value-score [0.0, 1.0] a product must have to be included. Products below this threshold are excluded before ranking.
querystringyesNatural-language product description, e.g. 'noise-cancelling wireless headphones under SGD 300'. Must be in English.

Structured output declared, but exposes no named fields.

No examples provided.