Webhooks

Webhooks notify your server when a project’s status changes, eliminating the need to poll.

Setup

Set a webhook URL when creating a project or via settings:

{
  "brief": "Your brief here",
  "webhook_url": "https://your-server.com/webhooks/eversince"
}

Or add one to an existing project:

curl -X PATCH https://eversince.ai/api/v1/projects/proj_abc123/settings \
  -H "Authorization: Bearer $EVERSINCE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "webhook_url": "https://your-server.com/webhooks/eversince" }'

The URL must use HTTPS.

Events

Webhooks fire on these status transitions:

Event	When
`running`	Agent started working
`generating`	Waiting for model outputs
`idle`	Work complete. Result ready or awaiting feedback
`failed`	Something went wrong
`rendering`	Final video render in progress

Cancelled projects do not fire webhook events.

Payload

Each webhook delivers the full project state (the same data returned by GET /projects/:id) plus an event field indicating the status transition that triggered the webhook.

{
  "id": "proj_abc123",
  "status": "idle",
  "mode": "autonomous",
  "output_type": "assembled",
  "event": "idle",
  "assembled_url": "https://...",
  "assembled_url_expires_at": "2025-03-16T10:30:00Z",
  "project_url": "https://eversince.ai/app/projects/...",
  "agent_message": "Your project is complete...",
  "assets": [
    {
      "ref": "a1b2c3d4",
      "type": "image-to-video",
      "url": "https://...",
      "model": "wan-2.6",
      "prompt": "Opening shot of the product on a clean background",
      "duration": 5.0,
      "aspect_ratio": "16:9",
      "source_image_url": "https://...",
      "source_video_url": null,
      "reference_image_url": null,
      "created_at": "2025-03-15T10:32:00Z"
    }
  ],
  "timeline": {
    "duration_seconds": 15.0,
    "aspect_ratio": "16:9",
    "skills": ["skill-cinema"],
    "scenes": [
      {
        "id": "scene_uuid",
        "ref": "a1b2c3d4",
        "type": "video",
        "position": 1,
        "duration": 5,
        "description": "Opening shot",
        "image_url": "https://...",
        "video_url": "https://...",
        "video_model": "wan-2.6",
        "image_model": "flux-2-max",
        "prompt": "Opening shot of the product on a clean background",
        "volume": 1.0,
        "fade_in": null,
        "fade_out": null
      }
    ],
    "audio": {
      "voiceover": null,
      "music": null,
      "tracks": []
    },
    "overlays": [],
    "captions": null
  },
  "created_at": "2025-03-15T10:30:00Z",
  "updated_at": "2025-03-15T10:35:00Z"
}

Signature verification

Webhook signing is optional. When a signing secret is configured for your account, every webhook includes signature headers for verification:

Header	Description
`X-Eversince-Signature`	`sha256=<hmac hex digest>`
`X-Eversince-Timestamp`	Unix timestamp (seconds)

Verification

The signature is an HMAC-SHA256 of {timestamp}.{raw body} using your signing secret.

import hmac
import hashlib

def verify_webhook(request, signing_secret):
    timestamp = request.headers["X-Eversince-Timestamp"]
    signature = request.headers["X-Eversince-Signature"]
    body = request.body.decode("utf-8")

    signed_content = f"{timestamp}.{body}"
    expected = "sha256=" + hmac.new(
        signing_secret.encode(),
        signed_content.encode(),
        hashlib.sha256
    ).hexdigest()

    return hmac.compare_digest(signature, expected)

const crypto = require("crypto");

function verifyWebhook(req, signingSecret) {
  const timestamp = req.headers["x-eversince-timestamp"];
  const signature = req.headers["x-eversince-signature"];
  const body = req.body; // raw string

  const signedContent = `${timestamp}.${body}`;
  const expected =
    "sha256=" +
    crypto.createHmac("sha256", signingSecret).update(signedContent).digest("hex");

  return crypto.timingSafeEqual(
    Buffer.from(signature),
    Buffer.from(expected)
  );
}

Delivery

Timeout: 10 seconds. Your endpoint must respond within this window.
Method: POST with Content-Type: application/json
Webhooks are delivered once. For reliability, confirm state with a GET /projects/:id call after receiving a webhook

Overview

Resources

API Reference

Setup

Events

Payload

Signature verification

Verification

Delivery

​Setup

​Events

​Payload

​Signature verification

​Verification

​Delivery

Setup

Events

Payload

Signature verification

Verification

Delivery