{"uid":"cap_5zfvlJSvzNpVQ3VdVeq9s","slug":"base-onchain-tools-portfolio-balances-d5155fe5","name":"Base Onchain Tools – Portfolio Balances","description":"Eleven read-only endpoints answering questions about Base mainnet that are tedious to assemble from raw RPC: what an unverified contract is actually able to do, whether a token transfer will revert and for what reason, what an arbitrary token is worth, and whether an address is safe to pay. Priced $0.001-$0.04 per call in USDC over x402. No account, no API key, no signup, no minimum, no rate limit to negotiate — the payTo address in the 402 response is the whole integration. Failed calls are not billed. The payment middleware cancels settlement on any 4xx or 5xx, so a malformed parameter or an upstream outage costs nothing. Answers are read live from Base mainnet at request time, with failover across five independent RPC providers. A batch that comes back incomplete is treated as a failure rather than returned with the missing entries as zeros, because a confident wrong answer costs a caller more than an error does. Scope is deliberately narrow: Base mainnet only, reads only, no keys held, nothing stored between requests.","url":"https://base-onchain-tools.dolerite.workers.dev/v1/base/portfolio","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["addresses"],"properties":{"addresses":{"type":"string","description":"Comma-separated Base addresses, max 20"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"count":2,"totals":{"eth":"0.5","usdc":"1200.5"}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","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":"$0.003/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_n440NumUmvHO11xTUlMWw","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns aggregated ETH and USDC balances across up to 20 Base mainnet addresses in a single call","exampleAgentPrompt":"What are the combined ETH and USDC balances across these three Base mainnet addresses: 0xABC...123, 0xDEF...456, and 0x789...GHI?","exampleUseCases":[{"title":"Multi-wallet treasury snapshot","prompt":"Can you pull the total ETH and USDC holdings across all five of our company's Base wallets: 0x111...aaa, 0x222...bbb, 0x333...ccc, 0x444...ddd, and 0x555...eee? I need a consolidated balance view."},{"title":"Check if addresses are funded before payment","prompt":"Before I send payments, tell me the current ETH and USDC balances for these two Base addresses: 0xAAA...111 and 0xBBB...222 — I want to make sure they're funded."},{"title":"DeFi portfolio monitoring for users","prompt":"Show me the combined onchain portfolio totals on Base for these ten addresses: 0x1a…, 0x2b…, 0x3c…, 0x4d…, 0x5e…, 0x6f…, 0x7g…, 0x8h…, 0x9i…, 0x10j… — what's the aggregate ETH and USDC?"}],"resultDescription":"A JSON object with the count of addresses queried, plus aggregated totals for ETH and USDC balances across all provided addresses (e.g. {\"count\": 2, \"totals\": {\"eth\": \"0.5\", \"usdc\": \"1200.5\"}}). Balances are read live from Base mainnet. If any address data is unavailable, the entire call fails rather than returning partial results with zeros.","failureModes":["Malformed or invalid Base addresses return a 4xx error (not billed)","More than 20 addresses in the list causes a parameter validation error","RPC failover exhausted across all five providers results in a 5xx (not billed)","Partial data retrieval treated as full failure — no zero-padded partial responses returned","Network timeout on Cloudflare Worker edge returns a 5xx error"],"whenToPreferThis":"Choose this endpoint when you need a quick, multi-address ETH and USDC balance rollup on Base mainnet without setting up RPC infrastructure or API keys. It's ideal for treasury dashboards, pre-payment checks, and portfolio monitoring across up to 20 addresses. The x402 pay-per-call model at $0.003 USDC makes it cost-effective for infrequent or bursty queries. Prefer alternatives if you need balances for tokens beyond ETH/USDC, need Ethereum mainnet or other chains, need historical balances, or require writes/transactions.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T00:41:33.735Z","isFirstParty":false}