hardhat

Add or modify a "util" in the Hardhat repo — a small, project-independent command exposed both as a built-in Hardhat task (`hardhat utils <ns> <cmd>`) and through the standalone `hhu <ns> <cmd>` binary, defined once in the `hhu` built-in plugin. Use when adding a new util task or namespace (like `constants zero-address`, `fetch block-number`, `convert pad`), or when a util needs something new such as a flag/option.

Analyzes the Hardhat regression benchmark history (the hardhat-benchmark-results repo's data.js) and recommends how many times each benchmark should run. It reads every commit's individual run times, computes each benchmark's per-commit coefficient of variation, removes outliers, takes the 95th-percentile CV, and sizes run counts for target noise levels (sigma = 3%, 1.5%, 1%, i.e. regression alert limits of 10% / 5% / 3%). Use when asked to right-size benchmark run counts, justify or revisit run counts, assess benchmark variance/noise, or decide whether to add or remove runs after changing the regression alert threshold.

Use when working with Hardhat 3 projects — writing or modifying Solidity tests, TypeScript tests, or any code touching hardhat.config.ts, the `hardhat` import, or `network.create()`. Covers test-layer choice, forge-std cheatcodes, the network connection API, `networkHelpers`, and the compile-then-typecheck workflow. For toolbox-specific guidance (clients, contract calls, assertions), also load the matching `hardhat-toolbox-*` skill.

Use alongside the `hardhat` skill when the project depends on `@nomicfoundation/hardhat-toolbox-mocha-ethers`. Covers the ethers helpers exposed on `network.create()`, contract interaction (`ethers.deployContract`, calling functions, `connect`), TypeChain-typed contract instances, and the chai matchers from `@nomicfoundation/hardhat-ethers-chai-matchers` (`.to.emit`, `.to.be.revertedWith*`, `.to.changeEtherBalance(s)`).

Use alongside the `hardhat` skill when the project depends on `@nomicfoundation/hardhat-toolbox-viem`. Covers the viem clients exposed on `network.create()`, contract interaction (`viem.deployContract`, `read`, `write`, `getContractAt`), and `viem.assertions` (revert / event / balance assertions).