# Synthex Forge Signed Snapshot

> Synthex Forge Signed Snapshot is a paid API for AI agents from x402.synthexforge.com, paid per call via x402, $0.3/call, status unknown (last checked 2026-10-23).

Creates a cryptographically signed (Ed25519 + SHA-256) attestation artifact from a caller-supplied data snapshot, returning a verifiable governance record on Base mainnet via x402 micropayment.

## Facts

- Endpoint: POST https://x402.synthexforge.com/v1/data/signed-snapshot?utm_source=zero.xyz
- Price: $0.3/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synthex-forge-signed-snapshot-accb1732
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ebhr9mDAsmQVXhZaUg1E4

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 synthex-forge-signed-snapshot-accb1732 -d '<json body>'
```

Example prompt: Take this dataset of market prices I fetched at Unix time 1718000000 — rows like [{key: 'BTC', value: '67000'}] with source citations from coinmarketcap.com — and create a signed snapshot attestation labeled 'BTC price snapshot' so I have a tamper-evident governance record of it.

## When to prefer this

Choose this endpoint when you need a cryptographically signed, verifiable attestation of a specific data snapshot — especially when source provenance, audit trails, or governance compliance are required. It is ideal for AI agents that need to prove the state of data at a point in time with Ed25519 signatures and SHA-256 hashing. Prefer it over simple logging when tamper-evidence and blockchain-anchored proof of data collection are needed. Not suitable for free-tier use cases, real-time streaming data, or scenarios where micropayment (USDC on Base) is not feasible.

## Known failure modes

- HTTP 402 returned if x402 USDC payment on Base mainnet (chain ID 8453) has not been completed or is malformed
- Empty or missing series array may cause validation failure or an attestation of an empty snapshot
- Invalid fetched_at timestamp (non-integer or far-future value) may be rejected or cause freshness anchor errors
- Malformed source citation objects (missing required fields) may result in incomplete provenance records
- Network or signing service outage returns non-200 error with no artifact created

## How this service works

Synthex Forge x402 Receive: 41 paid verification, attestation and governance endpoints (Ed25519 + SHA-256 signed artifacts) plus free verify/public-key/standard sibling routes. Paid routes answer HTTP 402 with an x402 v2 `payment-required` envelope (atomic USDC on Base mainnet, chain ID 8453). Free routes are declared with `security: []` per the x402scan discovery spec.

## Output

Returns a JSON object with {ok: true} confirming that the signed snapshot artifact was successfully created and recorded. The signed attestation (Ed25519 + SHA-256) is stored by Synthex Forge as a verifiable governance record, anchored to Base mainnet via x402 micropayment confirmation.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "series": {
   "type": "array",
   "items": {
    "type": "object"
   },
   "description": "Data rows of the snapshot: [{key, value, ...}]"
  },
  "sources": {
   "type": "array",
   "items": {
    "type": "object"
   },
   "description": "Source citations: [{url?, title?, publisher?, retrievedAt?}]"
  },
  "subject": {
   "type": "string",
   "description": "Optional human label for the thing being snapshotted."
  },
  "fetched_at": {
   "type": [
    "integer",
    "null"
   ],
   "description": "Unix seconds when the caller fetched the data (freshness anchor)."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synthex-forge-signed-snapshot-accb1732/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.synthexforge.com](https://www.zero.xyz/host/x402.synthexforge.com/llms.txt)