Validate one ISBN checksum and return its Open Library edition, work and author
Validate one ISBN checksum and return its Open Library edition, work and author records projected into one sourced CSL-JSON book item; invalid or absent ISBNs return an explicit refusal. The FOUR truth reading is true when found and neither on refusal.
Answeringour last check, 2026-10-03
1 of 1checks answered this week
27 msmedian answer time
$0.002listed price per call
$0.002price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
POST https://market.561.group/v1/book-record
| Category | Market data |
|---|---|
| Provider host | market.561.group |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 1 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-10-03 | valid payment request | 402 | $0.002 | 27 ms |
Example input (from the provider)
{
"body": {
"isbn": "9780670654000"
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"properties": {
"isbn": {
"description": "An ISBN-10 or ISBN-13, with or without hyphens.",
"type": "string"
}
},
"required": [
"isbn"
],
"type": "object"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method",
"bodyType",
"body"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"read": {
"enum": [
"neither",
"true",
"false",
"both"
]
},
"record": {
"description": "The normalized CSL-JSON book record when found.",
"type": "object"
},
"refusal": {
"description": "The invalid-checksum or not-found refusal when no record can be returned.",
"type": "object"
},
"sources": {
"items": {
"type": "string"
},
"type": "array"
}
},
"required": [
"sources",
"read"
],
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}