Transaction Simulator
When to use this skill
Use this skill BEFORE executing:
- •Complex swaps or trades
- •Smart contract interactions
- •Large transfers
- •DeFi operations (stake, lend, etc.)
What It Does
Simulates your transaction on a test environment to show:
- •✅ Will it succeed or fail?
- •📊 Expected output amounts
- •💰 Actual gas costs
- •⚠️ Warnings and errors
- •🔄 State changes preview
NO REAL TRANSACTION IS SENT - It's a safe preview!
Benefits
💰 Save Money
- •Avoid failed transactions (still cost gas!)
- •Preview slippage before swapping
- •Verify gas estimates
🛡️ Prevent Errors
- •Catch insufficient balance
- •Detect approval issues
- •Identify smart contract bugs
📊 Better Planning
- •See exact output amounts
- •Preview price impact
- •Understand state changes
Usage
python
from skills.transaction_simulator.scripts.simulate_tx import simulate_transaction
# Simulate a swap
tx_data = {
'from': 'TXXXabc...',
'to': 'SunSwap_Router',
'value': 100,
'data': '...' # Transaction data
}
result = await simulate_transaction(tx_data)
if result['success']:
print(f"Expected output: {result['output_amount']}")
print(f"Gas cost: {result['gas_used']}")
else:
print(f"Would fail: {result['error']}")
Output Example
✅ Successful Simulation
code
🎮 Transaction Simulation ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Operation: Swap 100 TRX → USDT Simulation: ✅ SUCCESS Expected Results: • Output: 14.85 USDT • Price: 1 TRX = 0.1485 USDT • Slippage: 0.5% • Price Impact: 0.02% Costs: • Gas Used: ~50,000 Energy • Est. Fee: 0.15 TRX ⏱️ Simulation Time: 1.2s ✅ Transaction will succeed 💡 Proceed with confidence!
❌ Failed Simulation
code
🎮 Transaction Simulation ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Operation: Swap 1000 TRX → SCAM_TOKEN Simulation: ❌ FAILED Error: "Transfer failed - Honeypot detected" Details: • Cannot sell this token after buying • Contract has blacklist function • Sell tax: 99% 🚨 DO NOT EXECUTE THIS TRANSACTION! Saved you: ~1000 TRX + gas fees
Technical Details
Simulation Methods
- •
TronGrid Simulation API (if available)
- •Most accurate
- •Uses actual blockchain state
- •
Local Fork Simulation
- •Creates temporary blockchain fork
- •Executes transaction locally
- •
Bytecode Analysis
- •Analyzes contract code
- •Predicts execution flow
Limitations
- •⚠️ Simulations use current blockchain state
- •🕐 Actual execution may differ if state changes
- •🔄 Time-sensitive operations may behave differently
- •📊 Gas estimates are approximate
Integration
Should auto-run before:
- •Any swap >$100 USD value
- •User's first interaction with a contract
- •Transactions to unverified contracts
- •User explicitly requests simulation
Safety
✅ 100% Safe - No real transactions sent ✅ No costs - Simulation is free ✅ Privacy - Simulations run locally when possible