# Base Address First Funder Lookup

> Base Address First Funder Lookup is a paid API for AI agents from api.x402node.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-16).

Returns the first incoming transfer that funded a Base blockchain address, including funder address, asset type, amount, block number, and timestamp.

## Facts

- Endpoint: GET https://api.x402node.dev/chain/first-funder
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-address-first-funder-lookup-bbfac7f9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_2j-fOaZNoPs53JmHLg2nL

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 base-address-first-funder-lookup-bbfac7f9
```

Example prompt: Who first funded this Base wallet — can you trace the original funding source for 0x4e3a...d7f2 and tell me the funder address, asset, amount, and when it happened?

## When to prefer this

Use this endpoint when you need to trace the origin of a wallet's initial funding on the Base network — particularly for sybil detection, burner wallet cluster analysis, compliance checks, or wallet provenance investigations. Prefer this over general balance or transaction history endpoints when the specific goal is identifying the first funder.

## Known failure modes

- Address has never received a transfer — no funder data available
- Invalid or malformed Base address returns an error
- Address exists on a different chain (not Base) — no results
- Rate limit or payment failure returns 402 or 429
- Network timeout if the Base RPC is temporarily unavailable

## How this service works

Trace the first incoming transfer that funded a Base address: funder address, asset, amount, block and time. Pairs with x402 dewash for sybil cluster and burner wallet analysis. wallet funding source, first funder, who funded this wallet, sybil detection, wallet provenance, burner cluster Accepts payment on Base or Solana — either network works.

## Output

Returns the funder's address, the asset used (e.g. ETH, USDC), the amount transferred, the block number, and the timestamp of the first incoming transfer that funded the queried Base address.

## Example request

```json
{
 "address": "0x1234567890123456789012345678901234567890"
}
```

## 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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "address": {
       "type": "string",
       "description": "Base address to trace (required)"
      }
     }
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-address-first-funder-lookup-bbfac7f9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.x402node.dev](https://www.zero.xyz/host/api.x402node.dev/llms.txt)