Get price estimates for multiple cards in a single request.

This endpoint allows batch processing of up to 100 card/grade combinations using CardHedge's correlated price estimation service.

Request Format:

{
  "items": [
    {"card_id": "abc123", "grade": "PSA 10"},
    {"card_id": "abc123", "grade": "PSA 9"},
    {"card_id": "xyz789", "grade": "BGS 9.5"}
  ]
}

Response Fields (per item):

• card_id: Card identifier from request
• grade: Grade from request
• price: Estimated price in USD (null if error)
• price_low: Lower bound of price estimate
• price_high: Upper bound of price estimate
• confidence: Confidence score (0-1)
• method: Estimation method ('direct' or 'correlated')
• freshness_days: Age of data used for estimation
• support_grades: Number of supporting grade data points
• grade_label: Grade label used for estimation
• provider: Grading provider (e.g., 'PSA', 'BGS')
• grade_value: Numeric grade value
• error: Error message if estimation failed for this item

Example curl:

curl -X POST -H "X-API-Key: your-api-key-here" \
     -H "Content-Type: application/json" \
     -d '{
       "items": [
         {"card_id": "1586812246197x228181943611293700", "grade": "PSA 10"},
         {"card_id": "1586812246197x228181943611293700", "grade": "PSA 9"}
       ]
     }' \
     "https://api.cardhedger.com/v1/cards/batch-price-estimate"

Returns batch results with individual success/error status per item. Maximum 100 items per request.

{
  "results": [
    {
      "card_id": "1586812246197x228181943611293700",
      "confidence": 0.45,
      "freshness_days": 1,
      "grade": "PSA 10",
      "grade_label": "PSA 10",
      "grade_value": 10,
      "method": "direct",
      "price": 1250,
      "price_high": 1325,
      "price_low": 1175,
      "provider": "PSA",
      "support_grades": 2
    },
    {
      "card_id": "1586812246197x228181943611293700",
      "confidence": 0.3809,
      "freshness_days": 2,
      "grade": "PSA 9",
      "grade_label": "PSA 9",
      "grade_value": 9,
      "method": "direct",
      "price": 385,
      "price_high": 407.92,
      "price_low": 362.08,
      "provider": "PSA",
      "support_grades": 1
    }
  ],
  "total_requested": 2,
  "total_successful": 2
}