# Multi-Source Transaction Verifier (lab.paidapis.net)

> Multi-Source Transaction Verifier (lab.paidapis.net) is a paid API for AI agents from lab.paidapis.net, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-15).

Verifies a blockchain transaction hash against multiple independent sources and returns a consensus confirmation status with a cryptographic signature.

## Facts

- Endpoint: GET https://lab.paidapis.net/api/verify-tx-multi-source
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/multi-source-transaction-verifier-lab-paidapis-net-68140148
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_QTiIGL323zBM5eY9NqcFp

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 multi-source-transaction-verifier-lab-paidapis-net-68140148
```

Example prompt: Can you verify transaction hash 0xabc123...def on Base mainnet by checking it against multiple sources and tell me whether consensus was reached and the block it was included in?

## When to prefer this

Choose this endpoint when you need tamper-evident, multi-source confirmation of a blockchain transaction rather than trusting a single RPC node. Ideal for payment verification pipelines, escrow release triggers, or fraud checks where you want a signed attestation and consensus signal across independent data providers rather than a single-node response.

## Known failure modes

- Invalid or malformed txHash returns an error
- Transaction not yet indexed by any source returns confirmed=null and consensusReached=false
- Fewer than threshold sources respond, leading to no consensus
- Transaction hash not found on Base mainnet returns empty or null confirmation
- Network timeout from upstream RPC/oracle sources causes partial results

## How this service works

Multi-source oracle: checks a Base tx hash against 3 independent RPC providers in parallel and only signs an attestation if all of them unanimously agree. If they disagree, the raw per-source breakdown is returned instead of a false attestation — stronger trust than the single-source oracle, priced accordingly.

## Output

Returns a JSON object containing: the chain name, the transaction hash, confirmation status (boolean or null), block number, number of agreeing sources, total sources checked, whether consensus was reached, a signer address, a cryptographic signature over the result, and a timestamp of when the check was performed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "txHash"
 ],
 "properties": {
  "txHash": {
   "type": "string",
   "description": "32-byte transaction hash to check."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "chain": {
   "type": "string"
  },
  "signed": {
   "type": "boolean"
  },
  "txHash": {
   "type": "string"
  },
  "sources": {
   "type": "array",
   "items": {
    "type": "object"
   }
  },
  "checkedAt": {
   "type": "string"
  },
  "confirmed": {
   "type": [
    "boolean",
    "null"
   ]
  },
  "signature": {
   "type": "string"
  },
  "blockNumber": {
   "type": [
    "integer",
    "null"
   ]
  },
  "totalSources": {
   "type": "integer"
  },
  "signerAddress": {
   "type": "string"
  },
  "agreeingSources": {
   "type": "integer"
  },
  "consensusReached": {
   "type": "boolean"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/multi-source-transaction-verifier-lab-paidapis-net-68140148/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from lab.paidapis.net](https://www.zero.xyz/host/lab.paidapis.net/llms.txt)