December 8, 2025 • 2 min read

Credential Verification API Integration Guide

Technical guide for integrating blockchain credential verification into your applications, HR systems, and business processes via API.

API integration developers technical

Why API Integration?

Manual credential verification doesn’t scale. API integration enables:

Automated verification workflows
Real-time status checks
System-to-system communication
Bulk verification operations

API Capabilities

Verification Endpoints

Check credential status programmatically:

GET /api/v1/verify/{credential_id}

Response includes:

Credential validity
Issuance details
Current status
Expiration information

Issuance Endpoints

Create credentials from your systems:

POST /api/v1/credentials

Include:

Recipient information
Credential type
Issuance date
Custom metadata

Status Endpoints

Query credential status:

GET /api/v1/credentials/{id}/status

Returns current validity and any changes.

Common Integration Patterns

HR System Integration

Candidate applies → 
ATS extracts credential links → 
API verifies credentials → 
Verified status in candidate profile

LMS Integration

Learner completes course → 
LMS triggers API → 
Credential issued → 
Learner notified

Access Control Integration

Employee scans badge → 
System checks credential API → 
Current = access granted
Expired = access denied

Authentication

API access requires:

API key for identification
Secret key for authentication
Optional OAuth for advanced scenarios

Keep credentials secure:

Never expose in client-side code
Use environment variables
Rotate keys periodically

Rate Limits

Standard limits:

Plan	Requests/minute	Requests/day
Starter	60	10,000
Professional	300	100,000
Enterprise	Custom	Custom

Handle rate limits gracefully with exponential backoff.

Error Handling

Common error responses:

400: Invalid request format
401: Authentication failed
404: Credential not found
429: Rate limit exceeded
500: Server error

Implement retry logic for transient errors.

Webhooks

Receive notifications for events:

Credential issued
Credential revoked
Credential expiring
Status changed

Configure webhook URL in settings to receive POST requests.

SDK Options

Available libraries:

JavaScript/Node.js
Python
PHP
Ruby
Java

SDKs handle authentication, error handling, and retries.

Testing

Use sandbox environment for:

Integration development
Testing without production data
Debugging issues

Sandbox credentials don’t affect production records.

Security Considerations

Use HTTPS only
Validate webhook signatures
Implement proper error handling
Log API usage for auditing
Secure credential storage

Conclusion

API integration automates credential verification and issuance for seamless workflows.

Access API documentation →

OnChainCert Team

OnChainCert

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