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Synapse API — Optimism Token Balances
x402
Synapse API — Optimism Token Balances 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).
Fetches ERC-20 token balances for a given wallet address on the Optimism (OP Mainnet) blockchain, optionally filtered by 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 token balance data for each specified ERC-20 contract (or all tokens held) for the given wallet on Optimism, including token quantities and likely token metadata such as symbol and decimals.
Example use cases
DeFi portfolio snapshot on Optimism
“Pull all the ERC-20 token balances for my wallet 0xde0B295669a9FD93d5F28D9Ec85E40f4cb697BAe on Optimism so I can see what I'm holding.”
Verify token receipt after bridge transfer
“After bridging, can you confirm that wallet 0xAb5801a7D398351b8bE11C439e05C5B3259aeC9B received USDC on Optimism? The USDC contract is 0x7F5c764cBc14f9669B88837ca1490cCa17c31607.”
Airdrop eligibility token check
“Check whether address 0x1234567890abcdef1234567890abcdef12345678 holds any of these three tokens on Optimism — OP at 0x4200000000000000000000000000000000000042, WETH at 0x4200000000000000000000000000000000000006, and SNX at 0x8700dAec35aF8Ff88c16BdF0418774CB3D7599B4.”
Technical details
Endpoint
POSThttps://synapse-api-brown.vercel.app/api/optimism/token/balancesWhen to prefer
Use this endpoint when you specifically need ERC-20 token balances on the Optimism (OP Mainnet) L2 network. Prefer this over generic on-chain tools if you want a pay-per-call, no-subscription model via x402 micropayments and are querying the Optimism chain specifically rather than Ethereum mainnet or other L2s.
Side effects
- Invalid or malformed wallet address returns an error
- Non-existent contract address returns zero balance or an error
- Network/RPC issues may cause timeouts
- Payment failure (x402) prevents the call from completing
- Empty contractAddresses array may return all tokens or nothing depending on implementation
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| owner | string | |
| contractAddresses | array |
Tags
x402
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