# BaseBuilder Trading Mempool Pending Transactions

> BaseBuilder Trading Mempool Pending Transactions is a paid API for AI agents from bb-trading-gold.vercel.app, paid per call via x402, $0.188704/call, status unknown (last checked 2026-10-23).

Retrieves or queries pending transactions currently in the blockchain mempool

## Facts

- Endpoint: POST https://bb-trading-gold.vercel.app/api/mempool/pending?utm_source=zero.xyz
- Price: $0.188704/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/basebuilder-trading-mempool-pending-transactions-1f5451da
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VS5nXj8q9bLmvpA9TEslc

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 basebuilder-trading-mempool-pending-transactions-1f5451da -d '<json body>'
```

Example prompt: Show me the current pending transactions in the Base mempool — I want to see any large unconfirmed swaps or trades waiting to be mined right now.

## When to prefer this

Use this endpoint when you need real-time visibility into unconfirmed transactions on the Base network, particularly for trading bots, MEV strategies, front-running detection, or monitoring large pending swaps before block confirmation.

## Known failure modes

- No pending transactions found — empty mempool response
- Payment of 0.188704 USDC not received — 402 Payment Required
- Invalid or malformed request body — 400 Bad Request
- Mempool data temporarily unavailable — 503 Service Unavailable
- Rate limit exceeded — 429 Too Many Requests
- Authentication or payment verification failure

## How this service works

BaseBuilder Trading API hub - 20 paid endpoints

## Output

A list of pending transactions currently sitting in the mempool, including transaction hashes, sender/receiver addresses, gas prices, values, and transaction data for trades or transfers not yet confirmed on-chain.

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/basebuilder-trading-mempool-pending-transactions-1f5451da/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from bb-trading-gold.vercel.app](https://www.zero.xyz/host/bb-trading-gold.vercel.app/llms.txt)