Asana Webhooks Skill

When to Use This Skill

• How do I receive Asana webhooks?
• How do I implement the Asana X-Hook-Secret handshake?
• How do I verify Asana webhook signatures (X-Hook-Signature)?
• How do I handle task, project, or story events (added, changed, removed, deleted, undeleted)?
• Why is my Asana webhook signature verification failing?

How Asana Webhooks Work

Asana webhooks have two phases that both POST to your target URL:

1. Handshake (once, at creation). When you call POST /webhooks, Asana sends a request carrying an X-Hook-Secret header and no X-Hook-Signature. Your endpoint must echo that same X-Hook-Secret back as a response header and return 200. Store the secret — it is the key for verifying every future delivery. This secret is shown only during the handshake.
2. Event deliveries (ongoing). Every later request carries an X-Hook-Signature header — a hex HMAC-SHA256 of the raw request body, keyed with the stored secret. The body is a batch: {"events": [...]}. Heartbeats arrive as {"events": []}.

Verification (core)

Distinguish the handshake from a normal delivery by which header is present, then HMAC the raw body and compare timing-safe.

Node:

const crypto = require('crypto');

function verifyAsanaSignature(rawBody, signatureHeader, secret) {
  if (!signatureHeader || !secret) return false;
  const expected = crypto.createHmac('sha256', secret).update(rawBody).digest('hex');
  try {
    return crypto.timingSafeEqual(
      Buffer.from(signatureHeader, 'hex'),
      Buffer.from(expected, 'hex')
    );
  } catch {
    return false; // wrong length / malformed hex
  }
}

// Handshake: echo X-Hook-Secret, store it, return 200.
// Delivery: verifyAsanaSignature(rawBody, req.headers['x-hook-signature'], storedSecret)

Python:

import hmac, hashlib

def verify_asana_signature(raw_body: bytes, signature_header: str, secret: str) -> bool:
    if not signature_header or not secret:
        return False
    expected = hmac.new(secret.encode(), raw_body, hashlib.sha256).hexdigest()
    return hmac.compare_digest(signature_header, expected)

For complete handlers with the handshake, event dispatch, and tests, see:

• examples/express/
• examples/nextjs/
• examples/fastapi/

Event Actions

Each event in the events array is compact — it names what changed, not the full object. Fetch full details with a follow-up API call using the resource gid.

Event object fields: action, resource ({ gid, resource_type }), parent, user, created_at, and (with filters) change.

For the full event reference, see Asana Webhooks Guide.

Important Headers

Environment Variables

# The X-Hook-Secret captured during the handshake for this webhook.
# In production, store one secret per webhook (keyed by webhook gid), not a single env var.
ASANA_WEBHOOK_SECRET=your_stored_x_hook_secret

# Optional: Personal Access Token used to create webhooks and fetch full resource details.
ASANA_ACCESS_TOKEN=your_personal_access_token

Local Development

# Start tunnel (no account needed)
npx hookdeck-cli listen 3000 asana --path /webhooks/asana

Create the webhook against the tunnel URL:

curl -X POST https://app.asana.com/api/1.0/webhooks \
  -H "Authorization: Bearer $ASANA_ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"data": {"resource": "<PROJECT_GID>", "target": "https://<your-tunnel>/webhooks/asana"}}'

Reference Materials

• references/overview.md - Asana webhook concepts, events, payloads
• references/setup.md - Creating webhooks via the API, the handshake
• references/verification.md - Signature verification details and gotchas