Build a Trade Document Endorsement Chain and Missing Evidence Tracker — implementation

## Build
Audit multi-party transferable records and bills of lading for title endorsement gaps. Assemble TradeTrust compliant endorsement sequences and issue automated evidence requests.

## User
Maritime trade documentation specialist

## Workflow
1. Incorporate electronic bills of lading and warehouse warrants into an endorsement tracker.
2. Verify token registry smart contract addresses and previous endorser public keys.
3. Identify breaks in the transfer of title or unverified intermediate holders.
4. Formulate a chronological endorsement lineage chart and generate missing evidence requests.

## Interface
Linear custody timeline graph showing endorsement transitions, signature status badges, and request ticket links.

## Data
Utilize TradeTrust document-store repository fixtures and sample JSON transferable records from source 1.
Starter examples below are synthetic. They are not downloaded records.

## Source
[TradeTrust](https://raw.githubusercontent.com/TradeTrust/tradetrust-website/master/README.md)
Adopts TradeTrust token registry identity proof formats and transferable record ownership verification steps.

## Tools
langgraph, ethers, pydantic.
LangGraph's cyclic state graphs model complex multi-party endorsement validations and pending inquiry loops.
Instruction-following API model skilled at legal document sequence evaluation and exception detection.

## Deliverables
Submit runnable source, pinned dependencies, setup commands, a working interface, example outputs, and a recorded end-to-end demo. Include tests and an action log.

## Acceptance
- Detects missing endorsements between intermediate holder transfers.
- Validates issuer token registry contract formats against Sepolia or Amoy networks.
- Generates targeted Request for Information (RFI) notices citing specific broken links.
- Emits structured endorsement chain summary payloads for downstream settlement.

## Starter Examples
```json
[
  {
    "input": {
      "bill_number": "TT-BL-99120",
      "endorsement_chain": [
        {
          "holder": "Exporter Corp",
          "transferred_to": "Bank Alpha",
          "signature_valid": true
        },
        {
          "holder": "Bank Alpha",
          "transferred_to": "Importer Corp",
          "signature_valid": true
        }
      ],
      "claimed_owner": "Importer Corp"
    },
    "expected_output": {
      "chain_intact": true,
      "missing_links": 0,
      "status": "CLEAR_FOR_CARGO_RELEASE",
      "rfi_issued": false
    }
  },
  {
    "input": {
      "bill_number": "TT-BL-99121",
      "endorsement_chain": [
        {
          "holder": "Exporter Corp",
          "transferred_to": "Bank Alpha",
          "signature_valid": true
        },
        {
          "holder": "Intermediary Trading",
          "transferred_to": "Importer Corp",
          "signature_valid": false
        }
      ],
      "claimed_owner": "Importer Corp"
    },
    "expected_output": {
      "chain_intact": false,
      "missing_links": 1,
      "status": "ENDORSEMENT_BREAK_DETECTED",
      "rfi_issued": true
    }
  }
]
```

## Safety
Acts purely as an analytical verification workspace; no on-chain token transfers or title releases are executed.
Use mock external writes. Require human review before any real deployment.