hydra-head-operator

OPERATOR SKILL: Executes Hydra Head operations that affect L1 state. Requires explicit human invocation.

When to use

• When ready to start hydra-node, init head, commit funds, or close/fanout
• After reviewing guidance from hydra-head

Operating rules (must follow)

• Confirm network and scripts tx id before starting
• Verify all peer configurations match
• REQUIRE explicit confirmation before Init, Close, Fanout
• Keep logs for debugging
• Test on devnet/preview before mainnet

Pre-flight checklist

[ ] Network: ___________
[ ] Hydra scripts tx id for network
[ ] Cardano node accessible (socket or Blockfrost)
[ ] Cardano signing key ready
[ ] Hydra signing key generated
[ ] Peer configs exchanged (vkeys + addresses)
[ ] Contestation period agreed

Execution workflow

Step 1: Generate Hydra key (if needed)

hydra-node gen-hydra-key --output-file hydra
# Creates hydra.sk and hydra.vk
chmod 600 hydra.sk

Step 2: Start hydra-node

hydra-node run \
  --node-id "participant-1" \
  --persistence-dir ./hydra-state \
  --cardano-signing-key cardano.sk \
  --hydra-signing-key hydra.sk \
  --hydra-verification-key peer1-hydra.vk \
  --hydra-verification-key peer2-hydra.vk \
  --cardano-verification-key peer1-cardano.vk \
  --cardano-verification-key peer2-cardano.vk \
  --peer "peer1-host:5001" \
  --peer "peer2-host:5001" \
  --api-host 0.0.0.0 \
  --api-port 4001 \
  --host 0.0.0.0 \
  --port 5001 \
  --testnet-magic 1 \
  --node-socket /path/to/node.socket \
  --hydra-scripts-tx-id <scripts-tx-id> \
  --contestation-period 120s \
  2>&1 | tee hydra-node.log

Step 3: Verify connectivity

# Check peers connected
curl -s localhost:4001/peers | jq .

# Check head status
curl -s localhost:4001/status | jq .

Step 4: Init head (REQUIRES CONFIRMATION)

⚠️ CONFIRM HEAD INIT ⚠️
Network: preprod
Participants: 3
Contestation period: 120s

Type 'init' to proceed:

# Via API
curl -X POST localhost:4001/init

# Or via hydra-tui
hydra-tui --connect localhost:4001

Step 5: Commit funds

# Prepare UTxO to commit
cardano-cli conway query utxo \
  --address <your-addr> \
  --testnet-magic 1

# Commit via API
curl -X POST localhost:4001/commit \
  -H "Content-Type: application/json" \
  -d '{"utxo": {"<txid>#<index>": {...}}}'

Step 6: Operate in head

# Submit L2 transactions through API
curl -X POST localhost:4001/submit \
  -H "Content-Type: application/json" \
  -d '{"transaction": "..."}'

Step 7: Close head (REQUIRES CONFIRMATION)

⚠️ CONFIRM HEAD CLOSE ⚠️
This will begin contestation period (120s).
All parties must remain online to contest if needed.

Type 'close' to proceed:

curl -X POST localhost:4001/close

Step 8: Fanout (after contestation)

# Wait for contestation period
# Then fanout
curl -X POST localhost:4001/fanout

# Verify L1 UTxOs
cardano-cli conway query utxo \
  --address <your-addr> \
  --testnet-magic 1

Safety / key handling

• Never share hydra.sk or cardano.sk
• Keep persistence-dir backed up
• Monitor logs during contestation
• Ensure all parties can contest if needed

References

• hydra-head (guidance skill)
• hydra-head-troubleshooter (if issues arise)
• shared/PRINCIPLES.md
• hydra.family docs