TransferChecked validates that the decimals parameter matches the mint’s decimals.
Use for Light→Light transfers when you need decimal verification.
For transfers involving SPL or Token 2022 accounts, use Transfer Interface instead.

Agent skill

npx skills add https://zkcompression.com

See the AI tools guide for dedicated skills.

Rust Client
Program

Guide
AI Prompt

Prerequisites

Dependencies

Cargo.toml

[dependencies]
light-token = "0.4.0"
light-client = { version = "0.19.0", features = ["v2"] }
solana-sdk = "2"
borsh = "0.10.4"
tokio = { version = "1", features = ["full"] }

Developer Environment

In-Memory (LightProgramTest)
Localnet (LightClient)
Devnet (LightClient)

Test with Lite-SVM (…)

# Initialize project
cargo init my-light-project
cd my-light-project

# Run tests
cargo test

use light_program_test::{LightProgramTest, ProgramTestConfig};
use solana_sdk::signer::Signer;

#[tokio::test]
async fn test_example() {
    // In-memory test environment 
    let mut rpc = LightProgramTest::new(ProgramTestConfig::default())
        .await
        .unwrap();

    let payer = rpc.get_payer().insecure_clone();
    println!("Payer: {}", payer.pubkey());
}

Connects to a local test validator.

npm
yarn
pnpm

npm install -g @lightprotocol/zk-compression-cli@beta

yarn global add @lightprotocol/zk-compression-cli@beta

pnpm add -g @lightprotocol/zk-compression-cli@beta

# Initialize project
cargo init my-light-project
cd my-light-project

# Start local test validator (in separate terminal)
light test-validator

use light_client::rpc::{LightClient, LightClientConfig, Rpc};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Connects to http://localhost:8899
    let rpc = LightClient::new(LightClientConfig::local()).await?;

    let slot = rpc.get_slot().await?;
    println!("Current slot: {}", slot);

    Ok(())
}

Replace <your-api-key> with your actual API key. Get your API key here.

use light_client::rpc::{LightClient, LightClientConfig, Rpc};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let rpc_url = "https://devnet.helius-rpc.com?api-key=<your_api_key>";
    let rpc = LightClient::new(
        LightClientConfig::new(rpc_url.to_string(), None, None)
    ).await?;

    println!("Connected to Devnet");
    Ok(())
}

Transfer with Decimal Check

Find the source code here.

Action
Instruction

use borsh::BorshDeserialize;
use light_client::rpc::Rpc;
use light_token_client::actions::{CreateAta, TransferChecked};
use rust_client::{setup, SetupContext};
use solana_sdk::{signature::Keypair, signer::Signer};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let SetupContext {
        mut rpc,
        payer,
        mint,
        associated_token_account,
        decimals,
        ..
    } = setup().await;

    // Create recipient associated token account
    let recipient = Keypair::new();
    let (_signature, recipient_associated_token_account) = CreateAta {
        mint,
        owner: recipient.pubkey(),
        idempotent: true,
    }
    .execute(&mut rpc, &payer)
    .await?;

    // TransferChecked validates decimals match the mint's decimals.
    // Only use for Light->Light transfers.
    // Use TransferInterface for all other transfers (Light, SPL or Token-2022).
    let sig = TransferChecked {
        source: associated_token_account,
        mint,
        destination: recipient_associated_token_account,
        amount: 1000,
        decimals,
    }
    .execute(&mut rpc, &payer, &payer)
    .await?;

    let data = rpc
        .get_account(recipient_associated_token_account)
        .await?
        .ok_or("Account not found")?;
    let token = light_token_interface::state::Token::deserialize(&mut &data.data[..])?;
    println!("Balance: {} Tx: {sig}", token.amount);

    Ok(())
}

use borsh::BorshDeserialize;
use light_client::rpc::Rpc;
use light_token::instruction::{
    get_associated_token_address, CreateAssociatedTokenAccount, TransferChecked,
};
use rust_client::{setup, SetupContext};
use solana_sdk::{signature::Keypair, signer::Signer};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Setup creates mint and associated token account with tokens
    let SetupContext {
        mut rpc,
        payer,
        mint,
        associated_token_account,
        decimals,
        ..
    } = setup().await;

    let transfer_amount = 400_000u64;

    // Create recipient associated token account
    let recipient = Keypair::new();
    let recipient_associated_token_account = get_associated_token_address(&recipient.pubkey(), &mint);

    let create_associated_token_account_instruction = CreateAssociatedTokenAccount::new(payer.pubkey(), recipient.pubkey(), mint)
        .instruction()?;

    rpc.create_and_send_transaction(&[create_associated_token_account_instruction], &payer.pubkey(), &[&payer])
        .await?;

    // TransferChecked validates decimals match the mint's decimals
    // Only use for Light->Light transfers.
    // Use TransferInterface for all other transfers (Light, SPL or Token-2022).
    let transfer_instruction = TransferChecked {
        source: associated_token_account,
        mint,
        destination: recipient_associated_token_account,
        amount: transfer_amount,
        decimals,
        authority: payer.pubkey(),
        max_top_up: None,
        fee_payer: None,
    }
    .instruction()?;

    let sig = rpc
        .create_and_send_transaction(&[transfer_instruction], &payer.pubkey(), &[&payer])
        .await?;

    let data = rpc
        .get_account(recipient_associated_token_account)
        .await?
        .ok_or("Account not found")?;
    let token = light_token_interface::state::Token::deserialize(&mut &data.data[..])?;
    println!("Balance: {} Tx: {sig}", token.amount);

    Ok(())
}

Transfer tokens with decimal validation

Open in Cursor

---
description: Transfer tokens with decimal validation
allowed-tools: Bash, Read, Write, Edit, Glob, Grep, WebFetch, AskUserQuestion, Task, TaskCreate, TaskGet, TaskList, TaskUpdate, TaskOutput, mcp__deepwiki, mcp__zkcompression
---

## Transfer tokens with decimal validation

Context:
- Guide: https://zkcompression.com/light-token/cookbook/transfer-checked
- Skills and resources index: https://zkcompression.com/skill.md
- SPL to Light reference: https://zkcompression.com/api-reference/solana-to-light-comparison
- Crates: light-token-client (actions), light-token (instructions), light-client (RPC)

TransferChecked validates that the decimals parameter matches the mint's decimals. Use for Light→Light transfers when you need decimal verification. For transfers involving SPL or Token 2022 accounts, use TransferInterface instead.

SPL equivalent: spl_token::instruction::transfer_checked → Light Token: TransferChecked

### 1. Index project
- Grep `light_token::|light_token_client::|solana_sdk|Keypair|async|TransferChecked|transfer_checked` across src/
- Glob `**/*.rs` for project structure
- Identify: RPC setup, existing token ops, entry point for transfer checked
- Check Cargo.toml for existing light-* dependencies and solana-sdk version
- Task subagent (Grep/Read/WebFetch) if project has multiple crates to scan in parallel

### 2. Read references
- WebFetch the guide above — follow the Rust Client tab
- WebFetch skill.md — check for a dedicated skill and resources matching this task
- TaskCreate one todo per phase below to track progress

### 3. Clarify intention
- AskUserQuestion: what is the goal? (new feature, migrate existing SPL code, add alongside existing)
- AskUserQuestion: does the project already have transfer operations to extend, or is this greenfield?
- AskUserQuestion: action-level API (high-level, fewer lines) or instruction-level API (low-level, full control)?
- Summarize findings and wait for user confirmation before implementing

### 4. Create plan
- Based on steps 1–3, draft an implementation plan: which files to modify, what code to add, dependency changes
- Verify existing Rpc/signer setup is compatible with the cookbook prerequisites (light_client::rpc::Rpc, solana_sdk::signature::Keypair)
- If anything is unclear or ambiguous, loop back to step 3 (AskUserQuestion)
- Present the plan to the user for approval before proceeding

### 5. Implement
- Add deps if missing: Bash `cargo add light-token-client light-token light-client --features light-client/v2`
- Follow the cookbook guide and the approved plan
- Write/Edit to create or modify files
- TaskUpdate to mark each step done

### 6. Verify
- Bash `cargo check`
- Bash `cargo test` if tests exist
- TaskUpdate to mark complete

### Tools
- mcp__zkcompression__SearchLightProtocol("<query>") for API details
- mcp__deepwiki__ask_question("Lightprotocol/light-protocol", "<q>") for architecture
- Task subagent with Grep/Read/WebFetch for parallel lookups
- TaskList to check remaining work

Guide
AI Prompt

Find a full code example at the end.

Transfer Checked with CPI

invoke (External signer)
invoke_signed (PDA signer)

use light_token::instruction::TransferCheckedCpi;

TransferCheckedCpi {
    source: source.clone(),
    mint: mint.clone(),
    destination: destination.clone(),
    amount,
    decimals,
    authority: authority.clone(),
    system_program: system_program.clone(),
    max_top_up: None,
    fee_payer: None,
}
.invoke()?;

use light_token::instruction::TransferCheckedCpi;

let signer_seeds = authority_seeds!(bump);

TransferCheckedCpi {
    source: source.clone(),
    mint: mint.clone(),
    destination: destination.clone(),
    amount,
    decimals,
    authority: authority.clone(),
    system_program: system_program.clone(),
    max_top_up: None,
    fee_payer: None,
}
.invoke_signed(&[signer_seeds])?;

Full Code Example

View the source code and full example with shared test utilities.

#![allow(unexpected_cfgs, deprecated)]

use anchor_lang::prelude::*;
use light_token::instruction::TransferCheckedCpi;

declare_id!("HXmfewpozFdxhM8BayL9v5541gwoGMXTrUoip5KySs2f");

#[program]
pub mod light_token_anchor_transfer_checked {
    use super::*;

    pub fn transfer_checked(
        ctx: Context<TransferCheckedAccounts>,
        amount: u64,
        decimals: u8,
    ) -> Result<()> {
        TransferCheckedCpi {
            source: ctx.accounts.source.to_account_info(),
            mint: ctx.accounts.mint.to_account_info(),
            destination: ctx.accounts.destination.to_account_info(),
            amount,
            decimals,
            authority: ctx.accounts.authority.to_account_info(),
            system_program: ctx.accounts.system_program.to_account_info(),
            max_top_up: None,
            fee_payer: None,
        }
        .invoke()?;
        Ok(())
    }
}

#[derive(Accounts)]
pub struct TransferCheckedAccounts<'info> {
    /// CHECK: Light token program for CPI
    pub light_token_program: AccountInfo<'info>,
    /// CHECK: Validated by light-token CPI
    #[account(mut)]
    pub source: AccountInfo<'info>,
    /// CHECK: Validated by light-token CPI
    pub mint: AccountInfo<'info>,
    /// CHECK: Validated by light-token CPI
    #[account(mut)]
    pub destination: AccountInfo<'info>,
    pub authority: Signer<'info>,
    pub system_program: Program<'info, System>,
}

Add transfer-checked CPI to an Anchor program

Open in Cursor

---
description: Add transfer-checked CPI to an Anchor program
allowed-tools: Bash, Read, Write, Edit, Glob, Grep, WebFetch, AskUserQuestion, Task, TaskCreate, TaskGet, TaskList, TaskUpdate, TaskOutput, mcp__deepwiki, mcp__zkcompression
---

## Add transfer-checked CPI to an Anchor program

Context:
- Guide: https://zkcompression.com/light-token/cookbook/transfer-checked
- Skills and resources index: https://zkcompression.com/skill.md
- SPL to Light reference: https://zkcompression.com/api-reference/solana-to-light-comparison
- Crate: light-token (TransferCheckedCpi)
- Example: https://github.com/Lightprotocol/examples-light-token/tree/main/programs/anchor/basic-instructions/transfer-checked

Key CPI struct: `light_token::instruction::TransferCheckedCpi`

### 1. Index project
- Grep `declare_id|#\[program\]|anchor_lang|Account<|Pubkey|invoke|transfer|decimals|amount` across src/
- Glob `**/*.rs` and `**/Cargo.toml` for project structure
- Identify: program ID, existing instructions, account structs, token accounts
- Read Cargo.toml — note existing dependencies and framework version
- Task subagent (Grep/Read/WebFetch) if project has multiple crates to scan in parallel

### 2. Read references
- WebFetch the guide above — review the Program tab CPI code samples
- WebFetch skill.md — check for a dedicated skill and resources matching this task
- TaskCreate one todo per phase below to track progress

### 3. Clarify intention
- AskUserQuestion: what is the goal? (add transfer-checked to existing program, new program from scratch, migrate from SPL transfer_checked)
- AskUserQuestion: should the authority be an external signer or a PDA? (determines invoke vs invoke_signed)
- Summarize findings and wait for user confirmation before implementing

### 4. Create plan
- Based on steps 1–3, draft an implementation plan: which files to modify, what code to add, dependency changes
- Follow the guide's step order: Build TransferCheckedCpi struct → call .invoke() or .invoke_signed()
- If anything is unclear or ambiguous, loop back to step 3 (AskUserQuestion)
- Present the plan to the user for approval before proceeding

### 5. Implement
- Add deps if missing: Bash `cargo add light-token anchor-lang@0.31`
- Follow the guide and the approved plan
- Write/Edit to create or modify files
- TaskUpdate to mark each step done

### 6. Verify
- Bash `anchor build`
- Bash `anchor test` if tests exist
- TaskUpdate to mark complete

### Tools
- mcp__zkcompression__SearchLightProtocol("<query>") for API details
- mcp__deepwiki__ask_question("Lightprotocol/light-protocol", "<q>") for architecture
- Task subagent with Grep/Read/WebFetch for parallel lookups
- TaskList to check remaining work

Introduction

Light Token Program

PDA Accounts

For Other Use Cases

Learn

Resources

Transfer Checked

Prerequisites

Transfer with Decimal Check

Transfer Checked with CPI

Full Code Example

Next Steps

Learn how to close Light Token accounts

Introduction

Light Token Program

PDA Accounts

For Other Use Cases

Learn

Resources

​Prerequisites

​Transfer with Decimal Check

​Transfer Checked with CPI

​Full Code Example

​Next Steps

Learn how to close Light Token accounts

Prerequisites

Transfer with Decimal Check

Transfer Checked with CPI

Full Code Example

Next Steps