Deterministic JSON evidence checks with signed verification evidence
Deterministic JSON evidence checks with signed verification evidence
Answeringour last check, 2026-10-18
1 of 1checks answered this week
1616 msmedian answer time
$0.01listed price per call
$0.01price 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://agent-economy.kgninja.dev/verify-evidence
| Category | Everything else |
|---|---|
| Provider host | agent-economy.kgninja.dev |
| 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 |
|---|---|---|---|---|
| 2026-10-18 | valid payment request | 402 | $0.01 | 1616 ms |
Example input (from the provider)
{
"body": {
"precheck_receipt_digest": "sha256:46dcfeb9495af1fd591447414866007f0915b8f5fdc20137091e4f4dabd80140",
"request": {
"assertions": [
{
"expected": "USD",
"op": "json_pointer_equals",
"path": "/invoice/currency"
}
],
"client_request_id": "agent-example-001",
"evidence": {
"content_base64": "eyJpbnZvaWNlIjp7ImN1cnJlbmN5IjoiVVNEIiwidG90YWwiOjEyNTB9fQ==",
"media_type": "application/json"
}
},
"spend_policy": {
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"max_amount_atomic": "10000",
"network": "eip155:8453",
"pay_to": "0x4D7d842536De9Eb491AE2300126B3CDdE7B0aDE3",
"policy_version": "agent-economy/precheck-policy/2.0"
}
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"additionalProperties": false,
"properties": {
"precheck_receipt_digest": {
"pattern": "^sha256:[a-f0-9]{64}$",
"type": "string"
},
"request": {
"additionalProperties": false,
"properties": {
"assertions": {
"items": {
"oneOf": [
{
"additionalProperties": false,
"properties": {
"expected_hex": {
"pattern": "^[a-f0-9]{64}$",
"type": "string"
},
"op": {
"const": "sha256_equals",
"type": "string"
}
},
"required": [
"op",
"expected_hex"
],
"type": "object"
},
{
"additionalProperties": false,
"properties": {
"op": {
"const": "json_pointer_exists",
"type": "string"
},
"path": {
"maxLength": 512,
"type": "string"
}
},
"required": [
"op",
"path"
],
"type": "object"
},
{
"additionalProperties": false,
"properties": {
"expected": {},
"op": {
"const": "json_pointer_equals",
"type": "string"
},
"path": {
"maxLength": 512,
"type": "string"
}
},
"required": [
"op",
"path",
"expected"
],
"type": "object"
},
{
"additionalProperties": false,
"properties": {
"expected_type": {
"enum": [
"null",
"boolean",
"number",
"string",
"array",
"object"
],
"type": "string"
},
"op": {
"const": "json_type_is",
"type": "string"
},
"path": {
"maxLength": 512,
"type": "string"
}
},
"required": [
"op",
"path",
"expected_type"
],
"type": "object"
}
]
},
"maxItems": 16,
"minItems": 1,
"type": "array"
},
"client_request_id": {
"maxLength": 64,
"minLength": 1,
"pattern": "^[A-Za-z0-9._:-]+$",
"type": "string"
},
"evidence": {
"additionalProperties": false,
"properties": {
"content_base64": {
"contentEncoding": "base64",
"contentMediaType": "application/json",
"maxLength": 87384,
"type": "string"
},
"media_type": {
"const": "application/json",
"type": "string"
}
},
"required": [
"media_type",
"content_base64"
],
"type": "object"
}
},
"required": [
"client_request_id",
"evidence",
"assertions"
],
"type": "object"
},
"spend_policy": {
"additionalProperties": false,
"properties": {
"asset": {
"pattern": "^0x[a-fA-F0-9]{40}$",
"type": "string"
},
"max_amount_atomic": {
"maxLength": 16,
"pattern": "^[1-9][0-9]*$",
"type": "string"
},
"network": {
"enum": [
"eip155:84532",
"eip155:8453"
],
"type": "string"
},
"pay_to": {
"pattern": "^0x[a-fA-F0-9]{40}$",
"type": "string"
},
"policy_version": {
"const": "agent-economy/precheck-policy/2.0",
"type": "string"
}
}