> ## Documentation Index
> Fetch the complete documentation index at: https://docs.b3os.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Smart Contract Read

Read any data from a smart contract without spending gas. Provide the contract ABI and function name to call view/pure functions on any EVM chain.

![Smart Contract Read logo](https://ai-icon.b3.fun/logo/ethereum)
Catalog action EVM Onchain

Read any data from a smart contract without spending gas. Provide the contract ABI and function name to call view/pure functions on any EVM chain.


## At a Glance

| Field | Value |
| --- | --- |
| Action ID | `evm-read` |
| Category | EVM Onchain |
| Connector | Not required |
| Requires gas | No |
| Funds movement | None declared |
| Tags | `blockchain`, `evm`, `read`, `view`, `contract`, `query`, `custom`, `abi` |

## Payload Schema

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `contractProjectId` | `string` | No | Select a deployed contract project or choose 'Custom' to enter address and ABI manually. |
| `chainId` | `number` | Yes | Chain ID \(1=Ethereum, 137=Polygon, 56=BSC, 8453=Base, etc.\) |
| `contractAddress` | `string` | No | The contract address to read from |
| `abi` | `string` | No | The ABI of the contract function\(s\) as a JSON string array. Can be full contract ABI or just the function signature needed. |
| `functionName` | `string` | Yes | The name of the view/pure function to call |
| `args` | `object` | No | Arguments for the function call as a JSON string array \(e.g., '\["0x123...", "1000"\]'\) or a native array. Optional if function has no arguments. |

## Result Schema

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `success` | `boolean` | Yes | - |
| `result` | `string` | Yes | The result of the contract call as a JSON string |
| `blockNumber` | `number` | No | The block number at which the read was performed |
| `decodedResult` | `string` | No | Human-readable decoded result when possible |

## Examples

**Workflow node**

```json
{
  "type": "evm-read",
  "payload": {
    "functionName": "example-functionName",
    "chainId": 8453
  },
  "children": []
}
```
  **Test with API**

```bash
curl -X POST "https://api.b3os.org/v1/actions/evm-read/test" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "inputs": {
    "functionName": "example-functionName",
    "chainId": 8453
  }
}'
```

**Use expressions for dynamic values**

Payload fields can use workflow expressions such as `{{$trigger.body.amount}}`, `{{$nodes.fetch.result.price}}`, and `{{$props.asset}}` when the value should come from a trigger, prior node, or reusable workflow prop.