{"name":"onyx_base_tx_explainer","tier":"metered","price_usdc":"0.05","endpoint":"https://onyx-actions.onrender.com/v1/onyx_base_tx_explainer","method":"POST","input_schema":{"type":"object","properties":{"tx_hash":{"type":"string","description":"0x-prefixed Base tx hash"}},"required":["tx_hash"]},"description":"Decode a Base mainnet transaction into a human-readable summary. Returns a one-line plain-English description of what happened (token transfers, swaps, approvals, contract deploys), ERC-20 transfer events with symbol resolution, balance changes per address, the function selector + decoded method name where it matches a known signature, gas used, fee in ETH, and tx status. Use when a trading agent needs to verify what a tx actually did before/after settlement, or when a wallet agent needs to explain a tx to its user. Direct equivalent of OATP's Solana tx_explainer ($0.10, 1,350 unique paying agents) — Onyx is the first to ship this on Base mainnet at $0.05.","when_to_use":"Use when a trading agent needs to verify a Base mainnet transaction actually did what it claims — confirm a swap landed at the expected price, audit a token transfer, or explain a contract interaction. Pre-trade safety check or post-trade verification.","vs_alternatives":"OATP charges $0.10 for the same primitive on Solana — Onyx is the first to ship this on Base mainnet, at half the price. Etherscan's free API has rate limits and no human-readable summary. Zapper's transaction-details ($0.0011) returns proprietary 'interpretation' rather than raw decoded structure.","example_request":{"tx_hash":"0xabababababababababababababababababababababababababababababababab"},"example_response":{"summary":"Swap with 2 token transfers (1 swap event).","status":"success","method":"swapExactETHForTokens","transfers":[{"symbol":"WETH","amount":1.0,"from":"0xrouter","to":"0xpool"},{"symbol":"USDC","amount":3450.5,"from":"0xpool","to":"0xagent"}],"swap_events":1,"elapsed_ms":280},"settle_to":"0x4326acB1A35e6B744BaAeA850c702Ca71dF86Cd5","network":"base-sepolia","facilitator":"https://x402.org/facilitator","payment_required":true,"free_introspection":true,"note":"GET this URL = free introspection card. POST with x402 payment header to call."}