# QuickBuild Base Token Info API

> QuickBuild Base Token Info API is a paid API for AI agents from quickbuild.quynguyenbac.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-21).

Looks up ERC-20 token metadata and optional holder balance on the Base blockchain by contract address

## Facts

- Endpoint: GET https://quickbuild.quynguyenbac.workers.dev/api/base/token?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/quickbuild-base-token-info-api-b5306cd9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_5hPS2ROlDSrNYqoloEsBB

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 quickbuild-base-token-info-api-b5306cd9
```

Example prompt: Look up the token metadata for the USDC contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base — I want to know the name, symbol, decimals, total supply, and whether it's using a proxy contract.

## When to prefer this

Choose this endpoint when you need on-chain ERC-20 token metadata specifically from the Base network (chainId 8453) including proxy detection, total supply, and optional holder balance — particularly when you want a pay-per-call micro-payment model via x402/USDC rather than managing API keys or subscriptions.

## Known failure modes

- Invalid or malformed contract address returns an error
- Non-contract (EOA) address returns isContract: false with no token fields
- Unknown or unverified tokens may return null for name/symbol/decimals
- Network or RPC errors may cause timeouts
- Payment not included or insufficient USDC causes 402 rejection

## How this service works

Landing pages ($15), Google Sheets/Apps Script automation ($10), scrapers, scripts & Telegram bots (from $15), broken-link + sitemap audit reports ($10). See a working demo first, pay after.

## Output

Returns a JSON object with the token's name, symbol, decimals, total supply (raw and formatted), whether it is ERC-20 compliant, whether it is a well-known token, the account type (contract vs EOA), code size in bytes, proxy implementation details (if any), and optionally the holder's balance — all for the specified Base chain contract address.

## 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": [],
     "properties": {
      "holder": {
       "type": "string",
       "description": "Optional address whose balance of this token to include."
      },
      "address": {
       "type": "string",
       "description": "Token / contract address on Base (0x + 40 hex). Optional: defaults to USDC 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "name": {
       "type": [
        "string",
        "null"
       ]
      },
      "proxy": {
       "type": [
        "object",
        "null"
       ]
      },
      "holder": {
       "type": "object"
      },
      "symbol": {
       "type": [
        "string",
        "null"
       ]
      },
      "address": {
       "type": "string"
      },
      "isErc20": {
       "type": "boolean"
      },
      "decimals": {
       "type": [
        "integer",
        "null"
       ]
      },
      "wellKnown": {
       "type": "boolean"
      },
      "isContract": {
       "type": "boolean"
      },
      "accountType": {
       "type": "string"
      },
      "totalSupply": {
       "type": [
        "object",
        "null"
       ],
       "properties": {
        "raw": {
         "type": "string"
        },
        "formatted": {
         "type": [
          "string",
          "null"
         ]
        }
       }
      },
      "codeSizeBytes": {
       "type": "integer"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "name": "USD Coin",
  "proxy": {
   "standard": "ZeppelinOS (e.g. Circle FiatTokenProxy)",
   "implementation": "0x2Ce6311ddAE708829bc0784C967b7d77D19FD779"
  },
  "symbol": "USDC",
  "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "chainId": 8453,
  "isErc20": true,
  "decimals": 6,
  "wellKnown": true,
  "isContract": true,
  "accountType": "contract",
  "totalSupply": {
   "raw": "4276257891842451",
   "formatted": "4276257891.842451"
  },
  "codeSizeBytes": 1852
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/quickbuild-base-token-info-api-b5306cd9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from quickbuild.quynguyenbac.workers.dev](https://www.zero.xyz/host/quickbuild.quynguyenbac.workers.dev/llms.txt)