Quick Start

Get up and running with LedgerLink API in under 5 minutes.

Prerequisites

API key (contact [email protected])
Basic understanding of REST APIs
Your favorite HTTP client (curl, Postman, or code)

Your First API Call

Using curl

curl -X GET "http://localhost:8090/api/v1/capabilities" \
  -H "Authorization: Bearer YOUR_API_KEY"

Using JavaScript

const response = await fetch('http://localhost:8090/api/v1/capabilities', {
  headers: {
    'Authorization': 'Bearer YOUR_API_KEY'
  }
});

const data = await response.json();
console.log(data);

Using Python

import requests

headers = {
    'Authorization': 'Bearer YOUR_API_KEY'
}

response = requests.get(
    'http://localhost:8090/api/v1/capabilities',
    headers=headers
)

data = response.json()
print(data)

Common Endpoints

Get Market Data

curl -X GET "http://localhost:8090/api/v1/market-data/candles?symbol=BTC-USD&interval=1h&limit=24" \
  -H "Authorization: Bearer YOUR_API_KEY"

Query Unified Engine

curl -X POST "http://localhost:8090/api/v1/query" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "connector": "market-data",
    "dataType": "candles",
    "filters": {
      "symbol": "BTC-USD"
    },
    "limit": 100
  }'

Screen an Address or Transaction (KYA / KYT)

Screening is asynchronous: submit a job, then poll the returned request_id. Send address to run KYA, or txid to run KYT. Programmatic callers authenticate with the x-api-key header.

# 1. Submit
curl -X POST "http://localhost:8090/api/v1/kyt/job" \
  -H "x-api-key: llk_your_api_key_here" \
  -H "Content-Type: application/json" \
  -d '{
    "address": "1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa",
    "chain": "bitcoin",
    "reference_id": "customer-12345"
  }'
# -> { "data": { "request_id": "0692ee28-...", "status": "queued" } }

# 2. Poll until status is "completed"
curl "http://localhost:8090/api/v1/kyt/job/0692ee28-..." \
  -H "x-api-key: llk_your_api_key_here"

See KYT & KYA for the full flow and response fields.

Response Format

All API responses follow a consistent format:

{
  "data": [...],
  "meta": {
    "total": 100,
    "page": 1,
    "limit": 50
  },
  "timestamp": "2026-01-20T12:00:00Z"
}

Error Handling

Errors return appropriate HTTP status codes with detailed messages:

{
  "error": {
    "code": "INVALID_PARAMETER",
    "message": "Invalid symbol format",
    "details": {
      "parameter": "symbol",
      "expected": "BASE-QUOTE format (e.g., BTC-USD)"
    }
  }
}

Next Steps

Authentication - Learn about API keys and security
Rate Limits - Understand rate limiting
API Reference - Explore all available endpoints
Market Intelligence - Dive into market data

Need Help?

📧 Email: [email protected]
💬 GitHub: github.com/ledgerlink
📚 Full API Reference: /api