# Xerxes Base Address Object Lookup

> Xerxes Base Address Object Lookup is a paid API for AI agents from ari001.tailb4ac3a.ts.net, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Resolves a Base blockchain address to a typed object (EOA, ERC-20 token, Uniswap V2/V3 pool, bare contract, or unreadable) along with the block number and block hash at which it was classified.

## Facts

- Endpoint: GET https://ari001.tailb4ac3a.ts.net/v1/base/object/:addr
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/xerxes-base-address-object-lookup-de9e5d50
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3SbUDdKhaDWe6sR_Q-OA5

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 xerxes-base-address-object-lookup-de9e5d50
```

Example prompt: What kind of address is 0x4200000000000000000000000000000000000006 on Base — is it a wallet, a token contract, or a Uniswap pool?

## When to prefer this

Use this endpoint when you need to definitively classify a Base network address into a known on-chain type (EOA, ERC-20, Uniswap V2/V3 pool, bare contract, or unreadable) at a specific block. It is more specific than a generic balance or ABI lookup because it returns a typed object rather than raw data, and it explicitly distinguishes pools from tokens and unreachable nodes from zero-value addresses.

## Known failure modes

- Invalid or malformed address (not a 20-byte 0x hex string) — likely 4xx validation error
- RPC node unavailable — address returned as 'unreadable' type rather than zeros
- Address exists but is a bare contract with no recognized ABI — returned as bare contract type
- Network timeout or infrastructure error — 5xx response

## How this service works

Use when an agent needs to know what a Base address is at a known block: EOA, ERC-20, Uniswap V2/V3 pool, bare contract, or unread. Returns a typed object plus blockNumber and blockHash. A token that is not a pool is a token. Dead RPC is unreadability, not zeros.

## Output

Returns a typed object indicating the address classification (EOA, ERC-20, Uniswap V2 pool, Uniswap V3 pool, bare contract, or unreadable), along with the blockNumber and blockHash at which the classification was made. If the RPC is unreachable the address is marked unreadable rather than returning zeros.

## 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"
    },
    "pathParams": {
     "type": "object",
     "required": [
      "addr"
     ],
     "properties": {
      "addr": {
       "type": "string",
       "description": "20-byte 0x address on Base"
      }
     }
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/xerxes-base-address-object-lookup-de9e5d50/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ari001.tailb4ac3a.ts.net](https://www.zero.xyz/host/ari001.tailb4ac3a.ts.net/llms.txt)