Our API Ecosystem

Two powerful APIs designed for different use cases

File Management & Stamping API

Credential Platform

Built on top of our Platform API, this higher-level API provides file upload, management, and blockchain stamping capabilities for credential platform customers.

  • 📁 File upload and management
  • 🔗 Blockchain stamping
  • ⚡ Real-time events
  • 🔄 Auto-expand groups

For:

Credential platform customers who need file storage and blockchain verification

Platform API

Enterprise

Our core enterprise API that provides atomic-level interactions with the ChainLetter platform. Works exclusively with hashes, not files.

  • 🔍 Hash verification
  • 📝 Direct blockchain operations
  • ⚙️ Low-level platform control
  • 🔐 Enterprise security

For:

Enterprise developers building custom solutions with direct platform access

How They Work Together

1

Platform API

Our foundational API that handles hash-based operations and blockchain interactions

↓
2

Credential Platform

Built using the Platform API, adds file upload capabilities and user-friendly interfaces

↓
3

File Management API

Provides simplified file operations for credential platform customers

Key Insight

The credential platform was built using our Platform API and doesn't transact in files, but only in hashes. We added the credential platform specifically to add file upload capability on top of our hash-based foundation.

Check out the video
👇👇👇

Webhook API

File Management & Stamping

Our Webhook API provides programmatic access to upload, manage, and stamp files on the blockchain. Perfect for integrating file storage and blockchain verification into your applications.

📁

File Management

Upload, list, and delete files with automatic group organization

🔗

Blockchain Stamping

Stamp entire collections to the blockchain for permanent verification

⚡

Real-time Events

Server-Sent Events for instant notifications of file operations

🔄

Auto-Expand Groups

Automatic group creation when size limits are reached

Requirements

🔑 API Key from Credential Management Tool
🔐 Secret Key for authentication
🌐 HTTPS endpoint for webhook delivery

Your Dedicated Webhook URL

https://{your-subdomain}.clstamp.com/webhook/{apikey}
🛡️

Security Best Practice

Make API calls from your server environment to keep your API key secure. Avoid exposing keys in client-side code or browser requests.

RESTful Commands

POST Upload files and create groups
GET List files and groups
PATCH Stamp collections to blockchain
DELETE Delete files from groups
GET Real-time event streaming
📖 View Full Documentation 📋 Download OpenAPI Spec

Platform API

Enterprise REST API

Our core enterprise Platform API provides atomic-level interactions with the ChainLetter platform. This full REST API works exclusively with hashes and provides direct blockchain operations for enterprise developers building custom solutions. Platform API keys represent Service Account users with their own token balance and ownership of stamped blockchain records.

🔍

Hash Verification

Verify CIDs and text content against blockchain records

📝

Direct Blockchain Operations

Create postmarks and interact directly with blockchain

⚙️

Low-Level Control

Atomic-level platform access for custom integrations

🔐

Enterprise Security

JWT authentication and service account management

Requirements

🏷️ Private Label API Key (Service Account)
🎫 JWT tokens for client authentication
💳 Service account with sufficient credits

API Endpoints

Production: https://verify.clstamp.com/api/v1/
Testing: https://staging-verify.clstamp.com/api/v1/
🛡️

Private Label System

Platform API keys are part of the private label system and represent Service Account users. These accounts have their own token balance and can be the owner of stamped blockchain records, unlike webhook API keys which are for file management operations.

📖 View Full Documentation 📋 View OpenAPI Specification