Onchain reads, decoded.
Guides, comparisons, integrations, reference docs, and trust reports for reading smart contract data from Claude, your code, n8n, or a REST client.
Using Chainlink Price Feeds Correctly: Staleness, Sequencer Uptime, and Decimals
The three checks a Chainlink price feed integration needs to be correct: staleness against the heartbeat, Base sequencer uptime, and decimals normalization without hardcoding 8.
Fixing "could not decode result data (value="0x")" in Ethers and Viem
Ethers and viem throw could not decode result data (value=0x) for four real reasons, from unresolved proxies to wrong chains. Diagnose each one and fix it fast.
ERC-8004 Explained: Query Onchain AI Agent Identity and Reputation with a REST Call
ERC-8004 gives AI agents a portable onchain identity and reputation record. Query the live Identity and Reputation registries with evmquery — no ABI, no SDK.
Why Your eth_call Loop Hits 429s (and How Multicall3 Fixes It)
A loop of eth_call calls works fine in dev, then throws 429 in production. Here's the real free-tier RPC limit behind it, and how Multicall3 fixes it.
evmquery vs. Raw viem: What a Falsifiable Benchmark Actually Shows
A falsifiable evmquery vs. raw viem comparison: real line counts, real round-trip counts, and an honest list of what evmquery still does not remove today.
How evmquery Resolves a Contract Read: ABI, Proxy, and Multicall3
A live walkthrough of what evmquery does between an address and a typed result: ABI resolution, proxy unwinding, and a Multicall3 batch, plus an honest look at portability.
Uniswap V3 Pool Data Without the SDK: Price, Liquidity, and Fees in One REST Call
Read sqrtPriceX96, tick, liquidity, and fee tier from any Uniswap V3 pool with a single POST request. No SDK, no ABI files, no RPC provider required.
Live On-Chain Data in LangGraph: Build an EVM Blockchain Tool in 40 Lines
Wire evmquery into a LangGraph ReAct agent to query live EVM contract data — token supplies, oracle prices, DeFi positions — with full state persistence across tool calls. No ABIs, no RPC node.
Live Onchain Data in Pydantic AI: Build an EVM Blockchain Tool in 30 Lines
Define a typed Pydantic AI tool that reads live EVM contract data — USDC balances, ETH prices, Aave positions — without ABIs, RPC nodes, or web3.py boilerplate.