Documentation
API Reference
Documentation
API Reference
Book a meeting
Linkedin
Github
  1. Webhooks
  • Introduction
  • Get started
    • Quickstart
    • Authentication
  • Core concepts
    • Agents
    • Phone numbers
    • Calls
    • Webhooks
  • Webhooks
    • Overview
    • Assistant request
    • Tool calls
    • Status update
    • End of call report
    • Security
  • Guides
    • Campaigns
    • xAI Realtime Integration
    • Voice selection psychology
    • Analysis templates
    • BYOK Setup
    • Call analysis
    • Call Transfers
    • Custom Tools
    • Sip Trunks
    • Tool templates
    • Voicemail detection
    • Autonomous silence detection
    • Billing
    • Error codes
    • Rate limits
    • Troubleshooting
  • Api's
    • Campaigns
    • Agents
    • Voices
    • BYOK
    • Analysis templates
    • Tool templates
    • Organization
    • Phone numbers
    • Sip trunks
    • Calls
    • Call control
    • Usage
    • Domains
Documentation
API Reference
Documentation
API Reference
Book a meeting
Linkedin
Github
  1. Webhooks

Security

When you configure a webhook_secret on your agent, Flireo signs all webhook requests. You should verify these signatures to ensure requests come from Flireo.

Signature Format#

Flireo uses HMAC-SHA256 to sign webhooks. The signature is included in the X-Webhook-Signature header.

How It's Calculated#

message = timestamp + "." + raw_request_body
signature = HMAC-SHA256(secret, message)

Verification Examples#

Python#

Node.js#

Go#

PHP#

Best Practices#

1.
Always verify in production - Never skip signature verification in production
2.
Use timing-safe comparison - Prevent timing attacks with constant-time comparison
3.
Check timestamp freshness - Optionally reject requests older than 5 minutes to prevent replay attacks
4.
Store secret securely - Use environment variables, not hardcoded values
5.
Log verification failures - Monitor for suspicious activity

Timestamp Validation#

Optionally validate the timestamp to prevent replay attacks:
See WebhookHeaders Schema for header details.
Modified at 2026-01-30 12:22:18
Previous
End of call report
Next
Campaigns
Built with