{"uid":"cap_H1MPeFT7cBdjo2P-c0e8i","slug":"basebrief-x402-base-chain-token-state-lookup-60773250","name":"BaseBrief x402 – Base Chain Token State Lookup","description":"Gas, balances, token metadata and allowances for $0.004 per result.","url":"https://basebrief-x402.savannah-5966.chatgpt.site/api/v1/base/token","method":"GET","headers":{},"bodySchema":{"type":"object","$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","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","required":["address"],"properties":{"address":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$","description":"Base mainnet address address."}},"additionalProperties":false}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","required":["evidence","limitations"],"properties":{"evidence":{"type":"object","additionalProperties":true},"limitations":{"type":"array","items":{"type":"string"}}},"additionalProperties":true}}}}},"responseSchema":{"type":"json","example":{"evidence":{"chain":"Base mainnet","chainId":8453,"blockNumber":"35123456","pointInTime":true},"limitations":["Point-in-time direct Base JSON-RPC evidence."]}},"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_QtBLLjauBrofEmkLS2ael","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":"Returns gas prices, token balances, token metadata, and allowances for a given Base mainnet address, charged at $0.004 per call via x402.","exampleAgentPrompt":"Can you pull the current token balances, gas price, and any ERC-20 allowances for the Base mainnet address 0xAbCd1234...5678 right now?","exampleUseCases":[{"title":"DeFi bot pre-trade state check","prompt":"Before executing this swap, check the token balance and current allowance for address 0xAbCd1234...5678 on Base mainnet so I know if I have enough funds and approval set."},{"title":"Portfolio dashboard data refresh","prompt":"Fetch the latest token balances and metadata for wallet 0xDeAd0000...BeeF on Base mainnet — I want to update my portfolio tracker with the current on-chain state."},{"title":"Gas cost estimation for a dApp","prompt":"What's the current gas price on Base right now for address 0x1111...2222? I need to estimate transaction fees before sending a batch of transfers."}],"resultDescription":"A JSON object containing point-in-time on-chain evidence for the queried Base mainnet address, including: current gas price, native and ERC-20 token balances, token metadata (symbol, decimals, name), allowances for specified spenders, the current block number, chain ID (8453), and a limitations array noting the data is a point-in-time snapshot from Base JSON-RPC.","failureModes":["Invalid address format (not matching ^0x[0-9a-fA-F]{40}$) returns a validation error","Missing required `address` query parameter returns a 400 bad request","Payment not provided or insufficient USDC causes x402 payment-required response","Base JSON-RPC node unavailability may cause timeouts or 5xx errors","Querying a non-existent or zero-balance address returns valid empty/zero data rather than an error"],"whenToPreferThis":"Choose this endpoint when you need real-time, point-in-time on-chain state for a Base mainnet address — specifically gas prices, token balances, ERC-20 metadata, or allowances — in a single cheap paid call ($0.004). Prefer it over general Ethereum RPC endpoints when you specifically need Base L2 data and want a structured, agent-friendly JSON response without managing your own RPC infrastructure. It is especially suitable for AI agents that need to check wallet state before executing DeFi operations or building portfolio dashboards.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T06:36:11.474Z","isFirstParty":false}