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Synapse API — Base Token Balances Lookup
x402
Synapse API — Base Token Balances Lookup is a paid API for AI agents from synapse-api-brown.vercel.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).
Retrieves ERC-20 token balances for a given wallet address on the Base blockchain, optionally filtered by specific contract addresses.
Price / call$0.01
Success—
StatusUnknown
How this service works
High-speed API suite for AI processing, web scraping, and smart data utilities across 57+ blockchain networks. Pay-per-call via x402.
Output
Returns a list of token balances associated with the specified owner wallet on the Base network, including balance amounts per token contract. When contract addresses are provided, results are scoped to those specific ERC-20 tokens only.
Example use cases
DeFi portfolio balance check
“Can you look up all the ERC-20 token balances for my wallet 0x742d35Cc6634C0532925a3b844Bc454e4438f44e on Base? I want to see everything I'm holding.”
Verify specific token receipt
“I'm expecting a USDC payment on Base — can you check if wallet 0xAbCd1234...5678 has a USDC balance at contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913?”
Multi-contract token audit
“Please fetch token balances for 0x1234567890abcdef1234567890abcdef12345678 on Base, checking these three contract addresses: 0xAaa..., 0xBbb..., and 0xCcc... — I need to audit what they hold.”
Technical details
Endpoint
POSThttps://synapse-api-brown.vercel.app/api/base/token/balancesWhen to prefer
Choose this endpoint when you need to check ERC-20 token balances specifically on the Base blockchain for a known wallet address. It is particularly useful when you want to filter balances by specific contract addresses rather than scanning all assets. Prefer this over general-purpose blockchain explorers when you need a programmatic, pay-per-call result with fast latency via the x402 micropayment protocol.
Side effects
- Invalid or malformed wallet address returns an error or empty result
- Unknown or non-existent contract address returns zero balance or error
- Rate limiting or payment failure (x402) blocks the call
- Network unavailability of Base RPC returns a timeout or service error
- Empty contractAddresses array may return all tokens or require at least one entry depending on implementation
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| owner | string | |
| contractAddresses | array |
Tags
x402
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