Function Overrides

RPC methods for intercepting the return value of a contract function on your Stagenet.

When an override is active, every call to that function — whether through eth_call or as an inner call from another contract — returns the fixed value you set, regardless of the contract’s actual code or storage. The override is applied inside the EVM, so a contract that staticcalls the overridden function sees the override too.

These methods back the SDK’s addFunctionOverride family.

Override shape

Every override has these fields:

Field	Type	Description
`id`	`string`	Generated id. Use it with update / remove / enable / disable.
`contractAddress`	`string`	Lowercased contract address
`functionAbi`	`string`	JSON-encoded ABI fragment for the overridden function
`inputParams`	`string[] \| null`	When non-null, the override only matches calls whose ABI-encoded inputs match these values exactly. `null` is a wildcard.
`returnValues`	`string[]`	String-encoded values matching the fragment’s outputs
`enabled`	`boolean`	Disabled overrides remain in the DB but are not applied
`createdAt`	`string`	ISO timestamp

When both a wildcard and an exact-input override exist for the same selector, the exact-input one takes precedence.

`dev_addFunctionOverride`

Install an override.

Parameter	Type	Description
`input`	`object`	See fields below

Input fields:

Field	Type	Description
`contractAddress`	`string`	Target contract
`functionAbi`	`string \| object`	JSON-encoded ABI fragment (or the fragment object — both accepted)
`inputParams`	`string[]?`	Omit (or pass `null`/`[]`) for a wildcard; pass values to match only that input
`returnValues`	`string[]`	One entry per output in the fragment

Returns the created override (see Override shape).

Example — override getCount() to always return 42:


curl -X POST <YOUR_STAGENET_RPC_URL> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "dev_addFunctionOverride",
    "params": [{
      "contractAddress": "0x1111111111111111111111111111111111111111",
      "functionAbi": "{\"type\":\"function\",\"name\":\"getCount\",\"inputs\":[],\"outputs\":[{\"type\":\"uint256\"}],\"stateMutability\":\"view\"}",
      "returnValues": ["42"]
    }]
  }'

Example — override balanceOf(0xabc…) to a specific value, leaving every other account untouched:


curl -X POST <YOUR_STAGENET_RPC_URL> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "dev_addFunctionOverride",
    "params": [{
      "contractAddress": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
      "functionAbi": "{\"type\":\"function\",\"name\":\"balanceOf\",\"inputs\":[{\"name\":\"account\",\"type\":\"address\"}],\"outputs\":[{\"type\":\"uint256\"}],\"stateMutability\":\"view\"}",
      "inputParams": ["0x1111111111111111111111111111111111111111"],
      "returnValues": ["1000000000"]
    }]
  }'

`dev_updateFunctionOverride`

Replace the returnValues of an existing override. contractAddress, the function selector, and inputParams are immutable — to change them, remove and re-add the override.

Parameter	Type	Description
`id`	`string`	Override id
`returnValues`	`string[]`	New return values

Returns the updated override.


curl -X POST <YOUR_STAGENET_RPC_URL> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "dev_updateFunctionOverride",
    "params": ["ckxyz...", ["100"]]
  }'

`dev_removeFunctionOverride`

Delete an override.

Parameter	Type	Description
`id`	`string`	Override id

Returns:


{ "id": "ckxyz...", "removed": true }

`dev_enableFunctionOverride` / `dev_disableFunctionOverride`

Toggle an override without deleting it. A disabled override stays in the DB but is not applied, so calls go through to the real contract.

Parameter	Type	Description
`id`	`string`	Override id

Returns the updated override.


curl -X POST <YOUR_STAGENET_RPC_URL> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "dev_disableFunctionOverride",
    "params": ["ckxyz..."]
  }'

`dev_getFunctionOverrides`

List every override on the Stagenet, most recent first.

Returns an array of overrides (see Override shape).


curl -X POST <YOUR_STAGENET_RPC_URL> \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "dev_getFunctionOverrides",
    "params": []
  }'

`dev_getFunctionOverridesByContract`

List overrides for a single contract.

Parameter	Type	Description
`contractAddress`	`string`	0x-prefixed Ethereum address

Returns an array of overrides.

Function Overrides

Override shape

dev_addFunctionOverride

dev_updateFunctionOverride

dev_removeFunctionOverride

dev_enableFunctionOverride / dev_disableFunctionOverride

dev_getFunctionOverrides

dev_getFunctionOverridesByContract