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

# Smart Contract API

> Read and write to any smart contract from a Blockradar wallet.

The Smart Contract API lets you interact with any on-chain smart contract directly from a Blockradar wallet without managing ABIs, gas estimation, or RPC providers yourself.

## What you can do

* Call read functions on any contract
* Execute write functions that modify on-chain state
* Use sign-only mode to sign contract interactions without broadcasting
* Estimate network fees for contract writes

## Endpoints

| Method | Endpoint                                                              | Description                                     |
| ------ | --------------------------------------------------------------------- | ----------------------------------------------- |
| `POST` | `/wallets/{walletId}/contracts/read`                                  | Read from a contract (master wallet)            |
| `POST` | `/wallets/{walletId}/contracts/write`                                 | Write to a contract (master wallet)             |
| `POST` | `/wallets/{walletId}/contracts/write/sign-only`                       | Sign-only contract write (master wallet)        |
| `POST` | `/wallets/{walletId}/contracts/network-fee`                           | Estimate fee for contract write (master wallet) |
| `POST` | `/wallets/{walletId}/addresses/{addressId}/contracts/read`            | Read from a contract (child address)            |
| `POST` | `/wallets/{walletId}/addresses/{addressId}/contracts/write`           | Write to a contract (child address)             |
| `POST` | `/wallets/{walletId}/addresses/{addressId}/contracts/write/sign-only` | Sign-only contract write (child address)        |
| `POST` | `/wallets/{walletId}/addresses/{addressId}/contracts/network-fee`     | Estimate fee for contract write (child address) |

<Card title="Full API Reference" icon="book" href="/en/api-reference/smart-contract/master-wallet-read">
  View all smart contract endpoints in the API Reference tab.
</Card>