Lowvyn Public API

What is this?

Lowvyn tracks daily prices across Amazon.ca, Walmart.ca, BestBuy.ca, Canadian Tire, Canada Computers, Newegg.ca, and Visions.ca, scores every product 0 to 100, and flags fake sales using full historical price data.

This is the REST surface. Same data as the MCP server (com.lowvyn/mcp), over plain HTTP+JSON for tools that don't speak MCP yet. Built for ChatGPT custom GPT actions, Perplexity, server-side integrations, and third-party developers.

Access and pricing

Commercial use of the API is paid. There is a free Developer tier for non-commercial and evaluation use, with a required Powered by Lowvyn link. Request access on the partner page.

Quick start

1. Request access on the partner page or by emailing contact@lowvyn.com. Once your account is enabled, open Account settings and generate a key under API Keys.
2. Copy your key, prefixed with lk_live_, when it appears. For your security it is shown only once.
3. Call any endpoint with X-API-Key: lk_live_… or Authorization: Bearer lk_live_….

OpenAPI 3.1 spec

The full machine-readable spec lives at the URLs below. Both are public, no auth required. Use the JSON form when configuring ChatGPT custom GPT actions (which only accept JSON).

Endpoints

Seven read-only GET endpoints. Every response includes a canonical lowvyn.com URL so AI consumers attribute citations correctly.

curl -H "X-API-Key: $KEY" https://api.lowvyn.com/api/public/v1/retailers

curl -H "X-API-Key: $KEY" https://api.lowvyn.com/api/public/v1/categories

curl -H "X-API-Key: $KEY" "https://api.lowvyn.com/api/public/v1/products/search?q=graco%20crib&max_price=300"

curl -H "X-API-Key: $KEY" https://api.lowvyn.com/api/public/v1/products/abc123def456

curl -H "X-API-Key: $KEY" https://api.lowvyn.com/api/public/v1/products/abc123def456/cheaper

curl -H "X-API-Key: $KEY" "https://api.lowvyn.com/api/public/v1/products/abc123def456/price-history?days=90"

curl -H "X-API-Key: $KEY" "https://api.lowvyn.com/api/public/v1/deals/verify?url=https%3A%2F%2Fwww.walmart.ca%2Fip%2F123&claimed_price=199.99"

Example response

GET /products/{id} returns:

{
  "id": "abc123def456",
  "title": "Graco Benton 5-in-1 Convertible Crib",
  "provider": "amazon",
  "retailerUrl": "https://www.amazon.ca/dp/B0B5JMV9QB",
  "currentPrice": 255.97,
  "currency": "CAD",
  "lowestPrice": 235.97,
  "highestPrice": 299.99,
  "lowvynScore": 62,
  "priceSignal": "average",
  "dealVerdict": "modest_deal",
  "canonicalUrl": "https://lowvyn.com/product-detail/abc123def456"
}

Error model

REST-idiomatic. HTTP status codes carry the success/failure signal. Error body shape:

{"error": "not_found", "message": "item \"ghost\" not found"}

Privacy and rate limits

• No personal data. We log API key usage (count, timing, error class) for operational telemetry. We do not log query parameters, request bodies, or anything personally identifiable about your end users.
• Rate limits by plan. From 10 requests per minute on the free Developer tier up to custom limits on Enterprise. Over-limit requests get HTTP 429 with a Retry-After header. See the plans.
• Attribution. The free Developer tier is for non-commercial and evaluation use and requires a visible "Powered by Lowvyn" link. Commercial use needs a paid plan. Use of the API is subject to the API Terms of Use.
• Coverage. Canadian retailers only (Amazon.ca, Walmart.ca, BestBuy.ca, Canadian Tire, Canada Computers, Newegg.ca, and Visions.ca). All prices in CAD.
• Stability. v1.x.y semver. Breaking changes only with a major version bump. Tool/endpoint additions or optional fields are backwards-compatible and don't bump the major.

Frequently asked questions