sncast Overview

Starknet Foundry sncast is a command line tool for performing Starknet RPC calls. With it, you can easily interact with Starknet contracts!

💡 Info At the moment, sncast only supports contracts written in Cairo v1 and v2.

⚠️ Warning Currently, support is only provided for accounts that use the default signature based on the Stark curve.

How to Use sncast

To use sncast, run the sncast command followed by a subcommand (see available commands):

$ sncast <subcommand>

If snfoundry.toml is present and configured with [sncast.default], url, accounts-file and account name will be taken from it. You can, however, overwrite their values by supplying them as flags directly to sncast cli.

💡 Info Some transactions (like declaring, deploying or invoking) require paying a fee, and they must be signed.

Examples

General Example

Let's use sncast to call a contract's function:

$ sncast call \
    --network sepolia \
    --contract-address 0x522dc7cbe288037382a02569af5a4169531053d284193623948eac8dd051716 \
    --function "pokemon" \
    --arguments '"Charizard"' \
    --block-id latest

command: call
response: [0x0, 0x0, 0x43686172697a617264, 0x9, 0x0, 0x0, 0x41a78e741e5af2fec34b695679bc6891742439f7afb8484ecd7766661ad02bf]

📝 Note In the above example we supply sncast with --account flag. If snfoundry.toml is present, and have this property set, value provided using this flags will override value from snfoundry.toml. Learn more about snfoundry.toml configuration here.

Network and RPC Providers

When providing --network flag, sncast will randomly select on of the free RPC providers. When using free provider you may experience rate limits and other unexpected behavior.

If using sncast extensively, we recommend getting access to a dedicated RPC node and providing its URL to sncast with --url flag.

Arguments

Some sncast commands (namely call, deploy and invoke) allow passing arguments to perform an action with on the blockchain.

Under the hood cast always send request with serialized form of arguments, but it can be passed in human-readable form thanks to the calldata transformation feature present in Cast.

In the example above we called a function with a deserialized argument: '"Charizard"', passed using --arguments flag.

⚠️ Warning Cast will not verify the serialized calldata. Any errors caused by passing improper calldata in a serialized form will originate from the network. Basic static analysis is possible only when passing expressions - see calldata transformation.

Using Serialized Calldata

The same result can be achieved by passing serialized calldata, which is a list of hexadecimal-encoded field elements.

For example, this is equivalent to using the --calldata option with the following value: 0x0 0x43686172697a617264 0x9.

To obtain the serialized form of the wished data, you can write a Cairo program that calls Serde::serialize on subsequent arguments and displays the results.

Read more about it in the Cairo documentation.

How to Use --wait Flag

Let's invoke a transaction and wait for it to be ACCEPTED_ON_L2.

$ sncast --account my_account \
    --wait \
    deploy \
	--network sepolia \
    --class-hash 0x0227f52a4d2138816edf8231980d5f9e6e0c8a3deab45b601a1fcee3d4427b02 \

Transaction hash: [..]
Waiting for transaction to be received. Retries left: 11
Waiting for transaction to be received. Retries left: 10
Waiting for transaction to be received. Retries left: 9
Waiting for transaction to be received. Retries left: 8
Waiting for transaction to be received. Retries left: 7
Received transaction. Status: Pending
Received transaction. Status: Pending
Received transaction. Status: Pending
Received transaction. Status: Pending
Received transaction. Status: Pending
Received transaction. Status: Pending
command: deploy
contract_address: [..]
transaction_hash: [..]

To see deployment details, visit:
contract: https://starkscan.co/search/[..]
transaction: https://starkscan.co/search/[..]

As you can see command waited for the transaction until it was ACCEPTED_ON_L2.

After setting up the --wait flag, command waits 60 seconds for a transaction to be received and (another not specified amount of time) to be included in the block.

📝 Note By default, all commands don't wait for transactions.