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

# Interacting with Contracts

> Call view functions and execute transactions on deployed Ralph contracts.

Once a contract is deployed you interact with it in two ways **view calls** that read state without a transaction, and **script executions** that change state and cost gas.

## View calls reading data

View calls are free and instant. Use them to read contract fields or call pure/view functions:

```bash theme={null}
curl -X POST "https://rpc.ralphstudio.xyz/{slug}/contracts/call-contract" \
  -H "Authorization: Bearer API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "group": 0,
    "address": "27Gsc5...",
    "methodIndex": 0,
    "args": []
  }'
```

```json theme={null}
{
  "returns": [
    {
      "type": "ByteVec",
      "value": "546f6b656e"
    }
  ],
  "gasUsed": 1000
}
```

`methodIndex` is the zero-based position of the function in the contract source. The first public function is `0`, the second is `1`, and so on.

## Passing arguments

Match the type names to the Ralph types declared in the function signature:

```bash theme={null}
curl -X POST "https://rpc.ralphstudio.xyz/{slug}/contracts/call-contract" \
  -H "Authorization: Bearer API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "group": 0,
    "address": "27Gsc5...",
    "methodIndex": 2,
    "args": [
      { "type": "Address", "value": "1DrDyTr9..." },
      { "type": "U256", "value": "1000000000000000000" }
    ]
  }'
```

| Ralph type | API type string | Example value           |
| ---------- | --------------- | ----------------------- |
| `U256`     | `"U256"`        | `"1000000000000000000"` |
| `I256`     | `"I256"`        | `"-500"`                |
| `Bool`     | `"Bool"`        | `true`                  |
| `ByteVec`  | `"ByteVec"`     | `"546f6b656e"`          |
| `Address`  | `"Address"`     | `"1DrDyTr9..."`         |

## State-changing calls TxScript

To execute a function that modifies state you build and submit a transaction using a TxScript. First build the unsigned transaction:

```bash theme={null}
curl -X POST "https://rpc.ralphstudio.xyz/{slug}/contracts/unsigned-tx/execute-script" \
  -H "Authorization: Bearer API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "fromPublicKey": "03a6b9c2d4e5f1...",
    "bytecode": "0101...",
    "attoAlphAmount": "1000000000000000000"
  }'
```

```json theme={null}
{
  "unsignedTx": "0201010...",
  "txId": "503bfb16...",
  "fromGroup": 0,
  "toGroup": 0,
  "gasAmount": 20000,
  "gasPrice": "100000000000"
}
```

Then sign the `txId` with your private key and submit:

```bash theme={null}
curl -X POST "https://rpc.ralphstudio.xyz/{slug}/transactions/submit" \
  -H "Authorization: Bearer API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "unsignedTx": "0201010...",
    "signature": "9e1a35b2..."
  }'
```

## Compile a TxScript on the fly

If you have Ralph source for a script you can compile it before building the transaction:

```bash theme={null}
curl -X POST "https://rpc.ralphstudio.xyz/{slug}/contracts/compile-script" \
  -H "Authorization: Bearer API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "code": "TxScript Withdraw(faucet: TokenFaucet) { faucet.withdraw{callerAddress!() -> ALPH: 1 alph}(callerAddress!(), 1 alph) }"
  }'
```

```json theme={null}
{
  "bytecodeTemplate": "0101...",
  "fields": {
    "names": ["faucet"],
    "types": ["Address"],
    "isMutable": [false]
  }
}
```

Use the returned `bytecodeTemplate` in the `execute-script` call above.

## Reading state after a transaction

After a state-changing transaction confirms, read the updated `mutFields`:

```bash theme={null}
curl "https://rpc.ralphstudio.xyz/{slug}/contracts/{contract-address}/state" \
  -H "Authorization: Bearer API_KEY"
```

```json theme={null}
{
  "mutFields": [
    {
      "type": "U256",
      "value": "999000000000000000000"
    }
  ]
}
```

## Next steps

<CardGroup cols={2}>
  <Card title="Contract events" icon="bolt" href="/smart-contracts/events">
    Query events emitted by your contract
  </Card>

  <Card title="Reading contracts via API" icon="file-code" href="/guides/reading-contracts">
    Full guide to view calls and state reads
  </Card>
</CardGroup>