Call when an agent needs the ERC-721 owner of token_id on an Ethereum contract,
Call when an agent needs the ERC-721 owner of token_id on an Ethereum contract, or an ERC-1155 balanceOf(owner, id) when standard is erc1155. A missing token errors. Read-only. No spend. Send JSON {"contract":"0x1111111111111111111111111111111111111111","token_id":"1"}. Exact $0.003 USDC on Base. Try unpaid POST /v1/sandbox/eth-nft-owner first.
Not tested: has real-world effectsour last check, 2026-10-20
0 of 0checks answered this week
n/amedian answer time
$0.003listed price per call
n/aprice it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
POST https://agentshelf.syntexa.ch/v1/eth-nft-owner
| Category | Code and developer |
|---|---|
| Provider host | agentshelf.syntexa.ch |
| Networks | eip155:8453 |
| Payment schemes | exact |
| Self-reported calls, 30 days | 1 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
We never call tools that send, buy, move money or file anything, not even without paying.
Example input (from the provider)
{
"body": {
"contract": "0x1111111111111111111111111111111111111111",
"token_id": "1"
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"additionalProperties": false,
"examples": [
{
"contract": "0x1111111111111111111111111111111111111111",
"token_id": "1"
}
],
"properties": {
"contract": {
"description": "NFT contract on Ethereum mainnet. Example: 0x1111111111111111111111111111111111111111. ownerOf or balanceOf is read-only.",
"examples": [
"0x1111111111111111111111111111111111111111"
],
"type": "string"
},
"owner": {
"description": "Account for ERC-1155 balanceOf(owner, token_id). Example: 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045. Required when standard is erc1155.",
"type": "string"
},
"standard": {
"default": "erc721",
"description": "Token standard. erc721 (default) uses ownerOf or tokenURI. erc1155 uses balanceOf(owner, id) or uri(id) with {id} substitution.",
"enum": [
"erc721",
"erc1155"
],
"type": "string"
},
"token_id": {
"description": "Token id as a decimal integer. Example: 1. A JSON number is accepted when it is a safe integer. A missing ERC-721 token errors.",
"examples": [
"1"
],
"pattern": "^(0|[1-9]\\d*)$",
"type": "string"
}
},
"required": [
"contract",
"token_id"
],
"type": "object"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method",
"bodyType",
"body"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"additionalProperties": false,
"examples": [
{
"balance": null,
"billed": true,
"contract": "0x1111111111111111111111111111111111111111",
"network": "eip155:1",
"ok": true,
"owner": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
"receipt_id": "rcpt_01EXAMPLE000000000000000",
"standard": "erc721",
"supports_erc1155": null,
"supports_erc721": true,
"token_id": "1",
"warnings": []
}
],
"properties": {
"balance": {
"examples": [
null
],
"type": [
"string",
"null"
]
},
"billed": {
"examples": [
true
],
"type": "boolean"
},
"contract": {
"examples": [
"0x1111111111111111111111111111111111111111"
],
"type": "string"
},
"network": {
"const": "eip155:1",
"examples": [
"eip155:1"
],
"type": "string"
},
"ok": {
"const": true,
"examples": [
true
],
"type": "boolean"
},
"owner": {
"examples": [
"0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"
],
"type": "string"
},
"receipt_id": {
"examples": [
"rcpt_01EXAMPLE000000000000000"
],
"type": "string"
},
"standard": {
"enum": [
"erc721",
"erc1155"
],
"examples": [
"erc721"
],
"type": "string"
},
"supports_erc1155": {
"examples": [
null
],
"type": [
"boolean",
"null"
]
},
"supports_erc721": {
"examples": [
true
],
"type": [
"boolean",
"null"
]
},
"token_id": {
"examples": [
"1"
],
"type": "string"
},
"warnings": {
"default": [],
"examples": [
[]
],
"items": {
"type": "string"
},
"type": "array"
}
},
"required": [
"ok",
"receipt_id",
"billed",
"network",
"contract",
"token_id",
"standard",
"owner",
"balance",
"supports_erc721",
"supports_erc1155"
],
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}