{"uid":"cap_jnqldmvUK6dih-59m-9Gx","slug":"cortex-cloud-token-balances-api-06de84cb","name":"Cortex Cloud Token Balances API","description":"One pay-per-call API for AI agents: optimization, AI, research, on-chain data, and automation — all settled in USDC on Base via x402. Discover via MCP and Bazaar, estimate free, pay per call. No API keys, no signup.","url":"https://api.cortexcloud.org/v1/data/token-balances","method":"GET","headers":{},"bodySchema":{"type":"object","properties":{"chain":{"type":"string","default":"ethereum"},"tokens":{"type":"array","items":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$"}},"address":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$"},"max_tokens":{"type":"integer","default":50,"maximum":200,"minimum":1}}},"responseSchema":{"type":"object","format":"application/json","example":{}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.004","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.004/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.004","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.004","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_cLaRgGKKlc7C38u1-UPt0","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.004","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Fetches ERC-20 token balances for a wallet address on a specified blockchain chain using the Alchemy Token API, paid via x402 USDC on Base.","exampleAgentPrompt":"What ERC-20 tokens does the wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 hold on Ethereum — show me up to 50 tokens?","exampleUseCases":[{"title":"Portfolio snapshot for a DeFi wallet","prompt":"Pull up all the ERC-20 token balances for wallet 0xAbCd1234abcd1234abcd1234abcd1234abcd1234 on Ethereum so I can see what tokens they're holding right now."},{"title":"Verify specific token holdings before a trade","prompt":"Check whether wallet 0x1234567890abcdef1234567890abcdef12345678 holds any USDC at contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 on Ethereum."},{"title":"Monitor whale wallet token positions","prompt":"Give me the top 100 ERC-20 token balances for wallet 0xBE0eB53F46cd790Cd13851d5EFf43D12404d33E8 on Ethereum — I want to track what this whale is holding."}],"resultDescription":"Returns a list of ERC-20 token holdings for the specified wallet address on the given chain, including token contract addresses and their respective balances. Results are capped at the requested max_tokens count (default 50, max 200).","failureModes":["Invalid wallet address format (not a valid 0x hex address) returns a validation error","Invalid or unsupported chain name returns an error or empty results","Malformed token contract address in the tokens filter array causes a validation error","Wallet has no ERC-20 token holdings returns an empty list","Alchemy upstream service outage or rate limit may cause 5xx or timeout errors","Payment failure via x402 (insufficient USDC balance) blocks the request"],"whenToPreferThis":"Choose this endpoint when you need on-chain ERC-20 token balance data for a wallet without managing Alchemy API keys directly. Ideal for agents that need to check crypto portfolio holdings, verify token ownership, or enrich wallet profiles. The x402 micropayment model ($0.004/call) makes it cost-effective for per-query usage without subscription overhead. Prefer this over raw RPC calls when you want normalized token balance output across chains.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-13T18:44:29.858Z","isFirstParty":false}