Cardano CLI Plutus Scripts Operator

cardano-cli-plutus-scripts-operator

OPERATOR SKILL: Executes Plutus script transactions. Requires explicit human invocation due to collateral risk.

When to use

• When ready to spend from a script address
• After reviewing guidance from cardano-cli-plutus-scripts

Operating rules (must follow)

• ALWAYS verify collateral UTxO is ADA-only
• Confirm script hash matches expected
• Validate datum/redeemer JSON before use
• REQUIRE explicit confirmation before submit
• Test on preprod/preview before mainnet

Pre-flight checklist

[ ] Network: ___________
[ ] Script file (.plutus) verified
[ ] Script hash matches on-chain
[ ] Datum JSON validated
[ ] Redeemer JSON validated
[ ] Collateral UTxO selected (ADA-only!)
[ ] Protocol parameters fresh

Execution workflow

Step 1: Verify script

# Get script hash
cardano-cli conway transaction policyid \
  --script-file script.plutus

# Derive script address
cardano-cli conway address build \
  --payment-script-file script.plutus \
  --testnet-magic 1 \
  --out-file script.addr

Step 2: Query script UTxO

cardano-cli conway query utxo \
  --address $(cat script.addr) \
  --testnet-magic 1

Step 3: Prepare collateral

# Must be ADA-only UTxO at your payment address
cardano-cli conway query utxo \
  --address <payment-addr> \
  --testnet-magic 1

# Select one with only ADA (no tokens)

Step 4: Build script spend

cardano-cli conway transaction build \
  --testnet-magic 1 \
  --tx-in <script-utxo>#<index> \
  --tx-in-script-file script.plutus \
  --tx-in-inline-datum-present \
  --tx-in-redeemer-file redeemer.json \
  --tx-in-collateral <collateral-utxo>#<index> \
  --tx-out <recipient>+<amount> \
  --change-address <payment-addr> \
  --out-file tx.unsigned

Step 5: Sign and submit

# Sign (collateral signer required)
cardano-cli conway transaction sign \
  --tx-file tx.unsigned \
  --signing-key-file payment.skey \
  --testnet-magic 1 \
  --out-file tx.signed

# ⚠️ CONFIRM before submit
echo "=== SCRIPT SPEND CONFIRMATION ==="
echo "Script: $(cat script.addr | head -c 20)..."
echo "Spending UTxO: <script-utxo>"
echo "Collateral: <collateral-utxo>"
echo "Output to: <recipient>"

cardano-cli conway transaction submit \
  --testnet-magic 1 \
  --tx-file tx.signed

Debugging failed scripts

# If script fails, check execution units
cardano-cli conway transaction build \
  ... \
  --calculate-plutus-script-cost cost.json

# Review cost.json for budget issues
cat cost.json | jq .

Safety / key handling

• Collateral is at risk if script fails unexpectedly
• Use minimal collateral (1-5 ADA typically sufficient)
• Keep datum/redeemer free of secrets
• Verify script logic on testnet first

References

• cardano-cli-plutus-scripts (guidance skill)
• shared/PRINCIPLES.md