# x402 Base Transaction Finality Check

> x402 Base Transaction Finality Check is a paid API for AI agents from x402-mcp.onrender.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-11).

Checks whether a specific Base (L2) transaction has reached finality on-chain, returning confirmation count, block status, and reorg-safety proof

## Facts

- Endpoint: GET https://x402-mcp.onrender.com/base/finality-check?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-base-transaction-finality-check-2164c292
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_B4XOChU-kQMeuYkCqbbjE

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 x402-base-transaction-finality-check-2164c292
```

Example prompt: Can you check whether transaction 0x7fe54ef102682c07d2091d5623cb86df8be1ca929ae4cfb90fbdd6e73eba2c40 on Base has reached finality and is safe from reorgs?

## When to prefer this

Use this endpoint when you need cryptographic certainty that a Base L2 transaction is irreversible — specifically when you need the 'finalized' checkpoint status (L1-confirmed, reorg-impossible), not just a high confirmation count. Prefer this over generic block explorers when your agent workflow requires a machine-readable, structured finality verdict with block-level evidence, especially in payment settlement, escrow release, or compliance logging scenarios on the Base network.

## Known failure modes

- Transaction hash not found on Base — returns null or error if the tx doesn't exist
- Transaction not yet finalized — returns status other than 'finalized' with lower confirmation count
- Network connectivity issues with Base RPC — may return timeout or upstream error
- Invalid transaction hash format — schema validation error on input
- Pending payment failure — x402 micropayment not processed, returns 402 Payment Required

## How this service works

MCP server for x402 HTTP micropayments with agent-commerce overlay

## Output

Returns a JSON object containing: the transaction hash, a human-readable explanation of finality status, the ISO timestamp of the check, a status string (e.g. 'finalized'), whether the tx is included, the tx block number, safe block, latest block, finalized block number, and total confirmations count.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "tx": "0x7fe54ef102682c07d2091d5623cb86df8be1ca929ae4cfb90fbdd6e73eba2c40",
  "why": "Block 49106777 is at or behind the chain's 'finalized' block (49115873) -- L1-confirmed, reorg is not possible.",
  "as_of": "2026-07-25T23:00:00+00:00",
  "status": "finalized",
  "included": true,
  "tx_block": 49106777,
  "safe_block": 49116306,
  "latest_block": 49116340,
  "confirmations": 9563,
  "finalized_block": 49115873
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-base-transaction-finality-check-2164c292/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-mcp.onrender.com](https://www.zero.xyz/host/x402-mcp.onrender.com/llms.txt)