# Used Car QuickCheck

> Used Car QuickCheck is a paid API for AI agents from x402-used-car-quickcheck-production.up.railway.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-13).

Compares a used car's asking price against up to 50 current dealer listings in Canada or the US, returning market pricing statistics, deal rating, and risk flags.

## Facts

- Endpoint: GET https://x402-used-car-quickcheck-production.up.railway.app/car-check?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/used-car-quickcheck-3f26dc01
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_nVOO5hCImzeZNUZaF6U46

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 used-car-quickcheck-3f26dc01
```

Example prompt: I'm looking at a 2020 Toyota Camry LE with 85,000 km on it and the dealer is asking $24,500 CAD in Ontario, Canada — can you run a market price check and tell me if it's a fair deal?

## When to prefer this

Choose this endpoint when you need a fast, low-cost ($0.01 USDC) used car market valuation backed by up to 50 real dealer listings in Canada or the US. It is ideal for pre-purchase deal assessment, negotiation preparation, and quick price sanity checks. Prefer it over generic price guides when you need quartile pricing, a deal rating with confidence score, and risk flags tailored to specific mileage and trim.

## Known failure modes

- Insufficient comparable listings found (low sample size reduces confidence)
- Invalid or unrecognized make/model/year combination returns an error
- Mileage provided in wrong unit (miles instead of km) leads to skewed results
- Price provided in wrong currency for the selected country
- Year outside supported range (1980–2030) rejected
- Missing required fields (make, model, year, mileage, price) returns validation error
- Payment failure (x402 protocol) if USDC balance is insufficient

## How this service works

Evaluate a used car before purchase. Compares the asking price with up to 50 current dealer listings in Canada or the U.S., matched by year, make, model, mileage and optional trim/location. Returns robust median and quartile pricing, deal rating, confidence, sample size and risk flags. Use for used-car price checks, negotiation prep and market comparisons.

## Output

Returns a structured JSON object with: matched vehicle details, market country and currency, asking price vs. median/quartile dealer prices, deal rating (e.g. great deal, fair, overpriced), confidence score, number of comparable listings found (up to 50), and risk flags such as high mileage or limited comparables.

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "make",
      "model",
      "year",
      "mileage",
      "price"
     ],
     "properties": {
      "city": {
       "type": "string",
       "description": "Optional city."
      },
      "make": {
       "type": "string",
       "description": "Vehicle manufacturer."
      },
      "trim": {
       "type": "string",
       "description": "Optional trim."
      },
      "year": {
       "type": "integer",
       "maximum": 2030,
       "minimum": 1980,
       "description": "Vehicle model year."
      },
      "model": {
       "type": "string",
       "description": "Vehicle model."
      },
      "price": {
       "type": "number",
       "description": "Asking price in CAD for CA or USD for US.",
       "exclusiveMinimum": 0
      },
      "state": {
       "type": "string",
       "description": "Optional province/state code."
      },
      "country": {
       "enum": [
        "CA",
        "US"
       ],
       "type": "string",
       "default": "CA",
       "description": "Comparison market."
      },
      "mileage": {
       "type": "integer",
       "minimum": 0,
       "description": "Current odometer reading in kilometres."
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "required": [
      "service",
      "version",
      "vehicle",
      "market",
      "asking_price",
      "mileage_km",
      "matching",
      "comparables",
      "pricing",
      "position",
      "risk_flags",
      "methodology",
      "data_freshness",
      "payment_network"
     ],
     "properties": {
      "market": {
       "type": "object"
      },
      "pricing": {
       "type": [
        "object",
        "null"
       ]
      },
      "service": {
       "type": "string"
      },
      "vehicle": {
       "type": "string"
      },
      "version": {
       "type": 
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/used-car-quickcheck-3f26dc01/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-used-car-quickcheck-production.up.railway.app](https://www.zero.xyz/host/x402-used-car-quickcheck-production.up.railway.app/llms.txt)