# ASIN402 Deal Check

> ASIN402 Deal Check is a paid API for AI agents from asin402.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-31).

Checks whether an Amazon product's current price is a good deal by comparing it against its 30/90/180-day price history and returning a buy verdict with reasoning.

## Facts

- Endpoint: GET https://asin402.com/api/deal-check?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/asin402-deal-check-83642e4a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_grDMozRloETEbOsibcTDq

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability asin402-deal-check-83642e4a
```

Example prompt: Is the Amazon price for ASIN B09G9FPHY6 on the US marketplace a good deal right now, or should I wait — give me the verdict and compare it to its historical averages?

## When to prefer this

Use this endpoint when you need a quick, opinionated verdict on whether an Amazon price is worth acting on now versus waiting. It is purpose-built for deal validation with fake-low outlier filtering and structured verdicts, making it superior to raw price-history lookups when you want an actionable recommendation rather than raw data. Prefer this over generic price trackers when you need a single call that returns both historical context and a clear buy/wait signal across 11 Amazon marketplaces.

## Known failure modes

- Invalid or non-existent ASIN returns an error or empty result
- Insufficient price history for a newly listed product may limit verdict accuracy
- Unsupported marketplace code returns an error
- Fake-low outlier offers are filtered but edge cases may still affect averages
- Product with no recent buy-box price may return null for current_price

## How this service works

Is this Amazon price a good deal? Buy now or wait. Price check against history for any ASIN: compares today's price with its 30/90/180-day averages and typical 180-day range (fake-low outlier offers filtered out) and returns a verdict (buy_now, fair_price, wait or verify_offer) with a one-line reason. Use before buying or recommending a product. Amazon price tracker / price drop check. 11 marketplaces. Free sample: /api/sample/deal-check

## Output

Returns a JSON object with the product title, current price, 30/90/180-day average prices, 180-day median, typical low and high for the 180-day window, percentage difference vs the 90-day average, a verdict string (buy_now, fair_price, wait, or verify_offer), a one-line reason explaining the verdict, the marketplace, currency, and a data timestamp.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "asin"
     ],
     "properties": {
      "asin": {
       "type": "string",
       "description": "Amazon ASIN, 10 characters (books: ISBN-10)"
      },
      "domain": {
       "type": "string",
       "description": "Marketplace: us, uk, de, fr, jp, ca, it, es, in, mx, br. Default us"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asin": {
       "type": "string"
      },
      "title": {
       "type": "string"
      },
      "reason": {
       "type": "string"
      },
      "avg_30d": {
       "type": "number"
      },
      "avg_90d": {
       "type": "number"
      },
      "verdict": {
       "type": "string"
      },
      "avg_180d": {
       "type": "number"
      },
      "currency": {
       "type": "string"
      },
      "data_as_of": {
       "type": "string"
      },
      "marketplace": {
       "type": "string"
      },
      "median_180d": {
       "type": "number"
      },
      "price_basis": {
       "type": "string"
      },
      "current_price": {
       "type": "number"
      },
      "typical_low_180d": {
       "type": "number"
      },
      "typical_high_180d": {
       "type": "number"
      },
      "percent_vs_90d_avg": {
       "type": "number"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "asin": "0735211299",
  "title": "Atomic Habits: An Easy & Proven Way to Build Good Habits & Break Bad Ones",
  "reason": "Price is at or near the low end of its usual range.",
  "avg_30d": 26.5,
  "avg_90d": 28.99,
  "verdict": "buy_now",
  "avg_180d": 29.5,
  "currency": "USD",
  "data_as_of": "2026-10-26T18:40:00.000Z",
  "marketplace": "us",
  "median_180d": 29.5,
  "price_basis": "buy_box",
  "current_price": 24.99,
  "typical_low_180d": 25.5,
  "typical_high_180d": 29.5,
  "percent_vs_90d_avg": -13.8
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/asin402-deal-check-83642e4a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from asin402.com](https://www.zero.xyz/host/asin402.com/llms.txt)