# Arkham x402 Polymarket Wallet USDC Balance

> Arkham x402 Polymarket Wallet USDC Balance is a paid API for AI agents from api.arkm.com, paid per call via x402, $0.2/call, status unknown (last checked 2026-09-15).

Returns the USDC balance for a specified wallet address on Polymarket, sourced from Arkham's on-chain intelligence data.

## Facts

- Endpoint: POST https://api.arkm.com/x402/polymarket/wallet/summary/balance
- Price: $0.2/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/arkham-x402-polymarket-wallet-usdc-balance-c3fdcba0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_dyGXg-ZHeQXZSKTdpTryE

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 arkham-x402-polymarket-wallet-usdc-balance-c3fdcba0 -d '<json body>'
```

Example prompt: What's the current USDC balance on Polymarket for wallet 0xBDDF61Af533fF524D27154e589d2D7A81510C684? Use Arkham's intelligence data to pull it.

## When to prefer this

Choose this endpoint when you need fast, programmatic access to a specific wallet's Polymarket USDC balance with Arkham's on-chain intelligence backing. Prefer it over manual block explorer lookups when building automated trading monitors, risk dashboards, or due diligence tools that need structured balance data for Polymarket accounts. The x402 pay-per-request model makes it cost-effective for infrequent or one-off lookups without a subscription.

## Known failure modes

- Invalid or malformed wallet address returns an error
- Address not found on Polymarket returns empty or zero balance
- Network congestion or on-chain indexing lag may cause stale data
- Insufficient USDC payment via x402 protocol causes request rejection
- Rate limiting if too many requests are made in a short window

## How this service works

Get Arkham Polymarket wallet balance summary. $0.20 per call.

## Output

Returns a JSON object containing the wallet's USDC balance as a string (which may be negative, indicating net exposure) and the queried wallet address. Example: {"usdcBalance": "-15906.549249", "userAddress": "0xBDDF61Af533fF524D27154e589d2D7A81510C684"}.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "addr": {
   "anyOf": [
    {
     "type": "string"
    },
    {
     "type": "number"
    },
    {
     "type": "boolean"
    },
    {
     "type": "array",
     "items": {
      "anyOf": [
       {
        "type": "string"
       },
       {
        "type": "number"
       },
       {
        "type": "boolean"
       }
      ]
     }
    }
   ],
   "description": "Required. Polymarket trade address (0x + 40 hex chars)."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "usdcBalance": "-15906.549249",
  "userAddress": "0xBDDF61Af533fF524D27154e589d2D7A81510C684"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/arkham-x402-polymarket-wallet-usdc-balance-c3fdcba0/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.arkm.com](https://www.zero.xyz/host/api.arkm.com/llms.txt)