# SignalHarness NFT Transfer History

> SignalHarness NFT Transfer History is a paid API for AI agents from signalharness.ai, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Retrieves the on-chain transfer history for a given NFT, returning provenance and movement records.

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/nft_transfer_history/invoke
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/signalharness-nft-transfer-history-d390572a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_EFtl8klND5h93dm6dlLWW

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability signalharness-nft-transfer-history-d390572a -d '<json body>'
```

Example prompt: Can you pull the full on-chain transfer history for NFT token ID 4201 from contract 0xBC4CA0EdA7647A8aB7C2061c2E118A18a936f13D on Base? I need to see every wallet that has ever held it.

## When to prefer this

Choose this endpoint when you need to retrieve on-chain NFT transfer provenance through a simple pay-per-call API without managing your own blockchain node or indexer. It is well-suited for agents that need occasional, on-demand NFT history lookups priced at $0.01 USDC per call with execution receipts for auditability.

## Known failure modes

- Invalid or malformed NFT contract address returns an error or empty history
- Token ID not found on-chain returns empty results with a warning
- Unsupported blockchain network returns a failure status
- Malformed request string causes a parsing error
- Payment failure (insufficient USDC) prevents execution and returns 402

## How this service works

Explore 330 pay-per-call x402 API services and 27 agent-native digital products, with Base USDC pricing, secure Polar checkout, and free discovery.

## Output

Returns a JSON object containing the NFT transfer history records including prior owners, transaction timestamps, and transfer events. Also includes a status field, warnings array, execution receipt with payment details, and a SHA-256 hash of the result for verification.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "nft_history_request": {
   "type": "string",
   "maxLength": 65536,
   "minLength": 2
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "History completeness depends on supplied records."
   ],
   "service_id": "nft_transfer_history",
   "evidence_scope": "caller_supplied_data",
   "nft_transfer_history": "{\"first_timestamp_ms\":1700000000000,\"last_timestamp_ms\":1700000000000,\"transfer_count\":1,\"transfers\":[{\"from\":\"0x0000000000000000000000000000000000000001\",\"log_index\":0,\"timestamp_ms\":1700000000000,\"to\":\"0x0000000000000000000000000000000000000002\",\"token_id\":\"1\",\"transaction_hash\":\"0xaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\"}]}"
  },
  "status": "succeeded",
  "receipt": {
   "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
   "usage": [],
   "status": "succeeded",
   "network": "eip155:8453",
   "artifacts": [],
   "endedAtMs": 0,
   "latencyMs": 0,
   "paymentId": "example-payment",
   "receiptId": "example-receipt",
   "requestId": "example-request",
   "serviceId": "nft_transfer_history",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "10000",
   "resultSha256": "6d8bf2864bd92022fe8c2513727acc46520e6b478d43b9cb853b810aeaf8e3fa",
   "serviceVersion": "1.0.0",
   "settlementReference": "0x0000000000000000000000000000000000000000000000000000000000000000"
  },
  "artifacts": [],
  "requestId": "example-request",
  "executionId": "example-execution"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/signalharness-nft-transfer-history-d390572a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from signalharness.ai](https://www.zero.xyz/host/signalharness.ai/llms.txt)