json-schema-validate
Validate LLM/agent JSON output against a JSON Schema (2020-12 subset) and auto-repair typical errors: code fences, trailing commas, numbers/booleans as strings, wrong enum case, single value instead of array, null optionals, extra or mis-cased keys, missing defaults. Returns errors, repaired JSON and fixes. POST recommended.
Endpoint
GET|POST https://forge-tools.dentreprise.workers.dev/api/json-schema-validate
Parameters
| Name | Required | Type | Description |
|---|---|---|---|
schema | Required | object | JSON Schema |
data | Required | string | JSON value or string to check |
repair | Optional | string | true (default) / false |
Example request (unpaid — expect 402)
curl -sS -D - "https://forge-tools.dentreprise.workers.dev/api/json-schema-validate?schema=%5Bobject+Object%5D&data=%7B%22age%22%3A+%2242%22%7D"
Example 402 challenge
The same object is also sent as a base64 PAYMENT-REQUIRED header. Amounts are atomic USDC units (6 decimals).
{
"x402Version": 2,
"error": "Payment required",
"resource": {
"url": "https://forge-tools.dentreprise.workers.dev/api/json-schema-validate",
"description": "Validate LLM/agent JSON output against a JSON Schema (2020-12 subset) and auto-repair typical errors: code fences, trailing commas, numbers/booleans as strings, wrong enum case, single value instead of array, null optionals, extra or mis-cased keys, missing defaults. Returns errors, repaired JSON and fixes. POST recommended.",
"mimeType": "application/json"
},
"accepts": [
{
"scheme": "exact",
"network": "eip155:8453",
"amount": "1000",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"payTo": "0x7B8bf45ac6AcbA6D4CFB626b57D3f5fF3C9C89F7",
"maxTimeoutSeconds": 120,
"extra": {
"name": "USD Coin",
"version": "2"
}
}
]
}Retry with payment
curl -sS "https://forge-tools.dentreprise.workers.dev/api/json-schema-validate?schema=%5Bobject+Object%5D&data=%7B%22age%22%3A+%2242%22%7D" \ -H "PAYMENT-SIGNATURE: $PAYMENT"
Example response
{
"valid": false,
"errors": [
{
"path": "$.age",
"msg": "expected integer, got string"
}
],
"repaired": {
"age": 42
},
"repaired_valid": true
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