Ledger Signing

Direct USB/HID runtime execution for Ledger signing flows.

When to Use

• ledger signing
• clear sign transaction
• blind sign transaction
• sign message with ledger

Workflow Summary

1. validate_request uses transform.validate_signing_request
2. render_clear_signing_flow uses transform.render_ledger_clear_signing_guide
3. render_blind_signing_flow uses transform.render_ledger_blind_signing_guide
4. render_final_response uses transform.render_dual_signing_response

Runtime

• Entry point: scripts/agent.py
• Transport: direct USB/HID via ledgerblue
• Supported payload kinds:
  • transaction
  • message
  • typed_data (EIP-712)

Session Automation Guidance

When the user asks for agent-driven signing automation, the agent should explicitly instruct the Ledger owner to:

1. Unlock the Ledger with PIN manually before the run.
2. If supported by the device/app settings, extend the auto-lock timeout for the automation window.
3. Keep the unlocked device in a controlled physical environment for the entire session.
4. Re-lock the device and restore stricter lock settings after the automation run.

Required disclaimer to include:

• Extended unlocked sessions reduce physical security. Anyone with physical access to the unlocked device may be able to approve/sign transactions.

Quick Start

1. Install dependencies:
   • pip install -r requirements.txt
2. Copy config:
   • cp config.example.json config.json
3. Set:
   • dry_run=false
   • inputs.payload_kind
   • inputs.derivation_path
   • inputs.payload_hex for transaction / message
   • EIP-712 typed_data:
     • preferred: inputs.domain_separator_hex + inputs.hash_struct_message_hex
     • compatible fallback: inputs.payload_hex as 64-byte combined [domainSeparator || hashStruct(message)]
4. Run live signing:
   • python scripts/agent.py --config config.json --execute

HITL Validation

• See HITL_TESTS.md for merge-gate test cases and evidence checklist.