# FiatDock Marketplace: Signal Sprint Base USDC Balance

> FiatDock Marketplace: Signal Sprint Base USDC Balance is a paid API for AI agents from fiatdock.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Fetches the USDC balance of any address on the Base network via a pay-per-call MCP-forwarded endpoint using x402 micropayment protocol

## Facts

- Endpoint: POST https://fiatdock.com/s/svc_4fed2ffb-54d5-45cb-8df7-91c680a8fee9
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fiatdock-marketplace-signal-sprint-base-usdc-balance-eb4f7f94
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_78iR3A8lD6yYrlLQT1m4W

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 fiatdock-marketplace-signal-sprint-base-usdc-balance-eb4f7f94 -d '<json body>'
```

Example prompt: Can you check the USDC balance of the address 0xAbC...1234 on Base using Signal Sprint?

## When to prefer this

Choose this endpoint when you specifically need the USDC balance (not ETH or other ERC-20 tokens) of an address on the Base network, and you want atomic pay-per-call pricing via x402 micropayments. Prefer this over full address intelligence endpoints when you only need USDC balance and want to minimize cost per call. Use when integrating with MCP-compatible agent toolchains that support x402 payment headers.

## Known failure modes

- Invalid or malformed Ethereum address returns an error response
- Address with zero USDC balance returns a valid response with zero amount
- Network congestion or RPC node issues may cause timeouts
- Malformed JSON-RPC body (wrong jsonrpc version or missing method/params) causes request rejection
- Payment failure via x402 protocol prevents the call from being processed

## How this service works

Pay-per-call: Signal Sprint Base USDC Balance

## Output

Returns the USDC token balance for the queried Base network address, delivered as a JSON-RPC 2.0 response forwarded from the seller's MCP endpoint, including the balance value in USDC units.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "method": {
   "type": "string",
   "description": "e.g. tools/call"
  },
  "params": {
   "type": "object",
   "description": "the seller's own tool name + arguments"
  },
  "jsonrpc": {
   "type": "string",
   "description": "\"2.0\" — the body is forwarded VERBATIM to the seller's MCP endpoint, so send whatever that server expects"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fiatdock-marketplace-signal-sprint-base-usdc-balance-eb4f7f94/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fiatdock.com](https://www.zero.xyz/host/fiatdock.com/llms.txt)