`hardhat_*` namespace

Utility methods that mimic Hardhat Network behavior (impersonation, snapshot resets, on demand mining, etc.).
Perfect for Hardhat test suites, Foundry scripts, or any framework that expects the Hardhat JSON-RPC surface.

curl -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"hardhat_impersonateAccount","params":["0x…address…"]}'

Method index

Impersonation

Method	✓ / ✗	Purpose
`hardhat_impersonateAccount`	✓	Start impersonating an address
`hardhat_stopImpersonatingAccount`	✓	Stop impersonation

Mining & automine

Method	✓ / ✗	Purpose
`hardhat_getAutomine`	▲	Always returns `true` (auto‑mine)
`hardhat_mine`	✓	Mine N blocks instantly

Chain reset

Method	✓ / ✗	Purpose
`hardhat_reset`	▲	Reset chain (blocknumber only when forked)

State modification

Method	✓ / ✗	Purpose
`hardhat_setBalance`	✓	Set account balance
`hardhat_setCode`	✓	Set account bytecode
`hardhat_setNonce`	✓	Set account nonce
`hardhat_setStorageAt`	✓	Set storage slot

Method reference

Hardhat’s full spec is in the Hardhat Network docs ↗︎.

hardhat_impersonateAccount

curl -s -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{
        "jsonrpc":"2.0","id":1,
        "method":"hardhat_impersonateAccount",
        "params":["0x…targetAddress…"]
      }'

hardhat_stopImpersonatingAccount

curl -s -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{
        "jsonrpc":"2.0","id":1,
        "method":"hardhat_stopImpersonatingAccount",
        "params":["0x…targetAddress…"]
      }'

hardhat_getAutomine ▲

Returns true.

curl -s -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"hardhat_getAutomine","params":[]}'

hardhat_mine

Mine one block or N blocks instantly.

# mine 1 block
curl -s -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"hardhat_mine","params":[]}'

# mine 5 blocks
curl -s -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","id":2,"method":"hardhat_mine","params":["0x5"]}'

hardhat_reset ▲

Resets the chain state.
Blocknumber rewinds only work while running in fork mode.

curl -s -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"hardhat_reset","params":[]}'

hardhat_setBalance

curl -s -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{
        "jsonrpc":"2.0","id":1,
        "method":"hardhat_setBalance",
        "params":["0x…targetAddress…", "0xDE0B6B3A7640000"]  // 1 ETH
      }'

hardhat_setCode

curl -s -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{
        "jsonrpc":"2.0","id":1,
        "method":"hardhat_setCode",
        "params":["0x…targetAddress…", "0x60006000…"]  // EVM bytecode
      }'

hardhat_setNonce

curl -s -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{
        "jsonrpc":"2.0","id":1,
        "method":"hardhat_setNonce",
        "params":["0x…targetAddress…", "0xA"]  // nonce = 10
      }'

hardhat_setStorageAt

curl -s -X POST http://localhost:8011 \
  -H 'content-type: application/json' \
  -d '{
        "jsonrpc":"2.0","id":1,
        "method":"hardhat_setStorageAt",
        "params":[
          "0x…targetAddress…",
          "0x0",                    // storage slot
          "0x0000000000000000000000000000000000000000000000000000000000000042"
        ]
      }'

Unimplemented stubs

The following methods are not yet implemented and will return Method not found:

hardhat_addCompilationResult
hardhat_dropTransaction
hardhat_metadata
hardhat_setCoinbase
hardhat_setLoggingEnabled
hardhat_setMinGasPrice
hardhat_setNextBlockBaseFeePerGas
hardhat_setPrevRandao

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