Amazon Product API — Getting Started — FetchLayer Docs

Getting Started

Find the products you care about, check their current prices in one batch, then read any one of them in full.

1. Get your API key

Create an account and generate a FetchLayer API key from your dashboard. There is no Amazon account, no Product Advertising API approval and no Associates tag involved.

Create free account →

2. Find the products

Price checks and product details take ASINs. If you have a keyword instead, search for it — every result carries its ASIN.

bash
curl -X POST https://api.fetchlayer.dev/amazon/search-products \
  -H "Authorization: Bearer ss-your-key" \
  -H "Content-Type: application/json" \
  -d '{"query":"mechanical keyboard","maxPrice":100,"marketplace":"com"}'

Tip

Already have an Amazon link? Send it to /resolve-url first — it returns the marketplace and ASIN, or the query and filters of a search URL, without contacting Amazon, and it does not consume a credit.

3. Check their prices

/price-check takes up to 20 ASINs or product URLs on one marketplace and returns the current price of each, with a per-product status. One product failing never fails the batch.

bash
curl -X POST https://api.fetchlayer.dev/amazon/price-check \
  -H "Authorization: Bearer ss-your-key" \
  -H "Content-Type: application/json" \
  -d '{"asins":["B09B8V1LZ3","B00FLYWNYQ","B07S98411N"],"marketplace":"com"}'

fast or full

The default mode: "fast" prices the whole batch in the fewest page loads and is what a polling price monitor should use; seller and stock status come back only where they are free. mode: "full" reads every product page and returns seller and stock status for every product, with a full product-page load per product. Both return the same price.

4. Read one product in full

/product-details returns the title, brand, price and list price, stock, seller, aggregate rating, images, feature bullets, categories and every variation with its own ASIN.

bash
curl -X POST https://api.fetchlayer.dev/amazon/product-details \
  -H "Authorization: Bearer ss-your-key" \
  -H "Content-Type: application/json" \
  -d '{"product":"https://www.amazon.de/dp/B0CFPWLGF2"}'

Same ASIN, different marketplace

A product URL carries its own marketplace. Passing a marketplace that contradicts it is a 400 rather than a guess, because the same ASIN can be a different product, or no product, on another Amazon.

Errors and retries

A 400 names the field to fix and a 404 means the product does not exist on that marketplace — neither is worth retrying. A 502 or 503 means Amazon did not give a usable answer this time; retry after a short pause. Read notes on every successful response too.

Error responses

Every error, on every route, is JSON in one shape: error (what went wrong, in words), status, code, retryable and requestId, which also comes as the X-Request-Id header. Branch on code and retryable rather than on the text; on a 5xx the text is generic. Quote requestId when reporting a problem.

json
{
  "error": "Missing required parameter: url",
  "status": 400,
  "missing": ["url"],
  "code": "invalid_input",
  "retryable": false,
  "requestId": "922874e3-c0d0-40d8-8866-d198af132420"
}
codeStatusRetryableMeaning
invalid_input400noThe request needs fixing; error names the field. A missing required parameter also lists it in missing.
unauthorized401noThe API key is missing or not valid.
insufficient_credits402noNothing left to spend: no credits, a used-up free trial, or a monthly allowance and credit balance both spent. error says which. Waiting does not help; topping up does.
forbidden403noThis key or account is not allowed this request.
not_found404noWhat the request names does not exist or is not public.
expired410noWhat the request refers to is no longer available; ask for it afresh.
quota_exceeded429noA request-rate limit was reached; error says which. Slow down before sending more.
cancelled499noThe caller closed or cancelled the request before it finished. The work was stopped and nothing was charged.
time_limit503yesYour timeoutMs ran out before there was anything to return; ask again, or allow more time.
temporarily_unavailable503yesNot available right now; ask again shortly.
posts_unavailable403noTikTok user videos: TikTok is not showing this account’s posts publicly right now. Asking again at once returns the same answer; nothing is charged.
store_unreachable503yesStore routes (Shopify, WooCommerce): the store itself can’t be reached right now — it may be offline. Ask again later. Where a store route doesn’t say so yet, an offline store is temporarily_unavailable.
upstream_error502yesThe source answered in a way that could not be used; ask again later.
internal_error500yesSomething failed on our side; ask again later, and quote requestId if it persists.
tool_error—noMCP only: a tool call failed in a way no other code describes; error says what.

More codes may be added; treat one you do not recognise by its retryable flag. Over MCP, a tool error carries the same fields in structuredContent, and as a JSON text block beside the message.

Next steps

Product overviewAmazon Product API: what it returns, pricing and use cases