# SignalHarness NFT Ownership Summary

> SignalHarness NFT Ownership Summary 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).

Analyzes and summarizes NFT ownership details from caller-supplied data about a wallet or collection

## Facts

- Endpoint: POST https://signalharness.ai/api/agent/services/nft_ownership_summary/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-ownership-summary-a0a19457
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_HIAMaMWj2jqUrGoxdfotV

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-ownership-summary-a0a19457 -d '<json body>'
```

Example prompt: Can you summarize the NFT ownership for this wallet — here's the data I have: wallet 0xABC123 on Base holds tokens from the Bored Apes and Pudgy Penguins collections. Give me a clean ownership summary.

## When to prefer this

Choose this endpoint when you have raw NFT ownership data (wallet info, token lists, collection details) that needs to be distilled into a human-readable summary. It is ideal for agent workflows where structured NFT data has already been fetched from a chain indexer and needs interpretation, or when you want a concise ownership narrative rather than raw on-chain data. It operates on caller-supplied data rather than fetching on-chain state itself, so pair it with a chain data source upstream.

## Known failure modes

- Empty or malformed nft_ownership_request string returns an error or empty summary
- Input exceeding 65,536 characters is rejected
- Ambiguous or unstructured input may produce warnings in the warnings array
- Network or payment processing failure returns a non-succeeded status

## How this service works

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## Output

Returns a JSON object containing an nft_ownership_summary string describing the NFT holdings, any warnings encountered during analysis, an evidence_scope field indicating the data came from caller-supplied input, a status field ('succeeded'), and a full receipt with payment ID, request ID, execution ID, network, and result hash for auditability.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "replay": false,
  "result": {
   "warnings": [
    "Summary is not a current ownership lookup."
   ],
   "service_id": "nft_ownership_summary",
   "evidence_scope": "caller_supplied_data",
   "nft_ownership_summary": "{\"owner_count\":1,\"owners\":{\"0x0000000000000000000000000000000000000001\":[\"1\",\"2\"]},\"token_record_count\":2}"
  },
  "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_ownership_summary",
   "executionId": "example-execution",
   "startedAtMs": 0,
   "amountAtomic": "10000",
   "resultSha256": "edac9af878a53b3c72486d0d7b48f999913c34624107775125814049630f8840",
   "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-ownership-summary-a0a19457/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)