# Seneschal Private Historical Chain Scan

> Seneschal Private Historical Chain Scan is a paid API for AI agents from api.seneschal.space, paid per call via x402, $0.5/call, status unknown (last checked 2026-09-15).

Scan historical Monero or Zcash blockchain data using a view key to retrieve past transactions and notes for a given address up to a specified block height

## Facts

- Endpoint: POST https://api.seneschal.space/v1/private/historical
- Price: $0.5/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/seneschal-private-historical-chain-scan-60fcc756
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap__4PG0EUzWBY1Tlvqt7Y-j

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 seneschal-private-historical-chain-scan-60fcc756 -d '<json body>'
```

Example prompt: Scan my Monero wallet history using my view key — address is 4Abc...xyz, view key is abc123...def, scan up to block height 3200000 starting from birthday height 2900000, and include all received notes.

## When to prefer this

Use this endpoint when you need a retrospective, historical view of incoming transactions on a Monero or Zcash wallet using only a read-only view key — particularly when you want to audit past receipts, reconstruct wallet history, or verify past payments without any live monitoring. Prefer this over the live-watch webhook endpoint when the payments have already occurred and you need historical data rather than real-time alerts.

## Known failure modes

- Invalid or mismatched view key / address pair returns authentication or decryption error
- Unsupported chain value (anything other than 'monero' or 'zcash') returns validation error
- toHeight exceeds current chain tip — may return partial results or error
- Missing view key returns 400 bad request
- Address provided for Zcash UFVK scan is ignored or causes confusion
- Payment not received or insufficient x402 USDC balance results in 402 Payment Required
- Very wide block range scans may time out or be rate-limited

## How this service works

Pay-per-call services for the agent economy: a webhook the moment a Monero or Zcash payment lands at your address (view-key only), single-fact x402 data APIs, a paid public notice board, a stablecoin gas paymaster and a permissionless Ethereum block builder. No account, no API key — pay in USDC on Base or in XMR/ZEC.

## Output

A structured list of historical transactions and/or notes received at the specified Monero or Zcash address up to the given block height, extracted using the provided view key without requiring spending authority.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "chain": {
   "enum": [
    "monero",
    "zcash"
   ],
   "type": "string"
  },
  "address": {
   "type": "string",
   "description": "Required for Monero; ignored for Zcash UFVK scans."
  },
  "viewKey": {
   "type": "string"
  },
  "toHeight": {
   "type": "integer"
  },
  "includeNotes": {
   "type": "boolean"
  },
  "birthdayHeight": {
   "type": "integer"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "chain": "zcash",
  "elapsed_ms": 8421,
  "scanned_at_ms": 1765532000000,
  "birthdayHeight": 2400000,
  "view_key_handling": "streamed to NFPT in memory only; not persisted to gateway DB or logs"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/seneschal-private-historical-chain-scan-60fcc756/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.seneschal.space](https://www.zero.xyz/host/api.seneschal.space/llms.txt)