{
"subscriberId": "wh_1a2b3c4d5e6f7a8b9c0d1e2f",
"chokepointId": "suez",
"score": 72,
"alertThreshold": 50,
"triggeredAt": "2026-07-04T12:34:56Z",
"reason": "navigational_warning"
}Chokepoint disruption alert outbound signed
WorldMonitor POSTs this event to the callbackUrl you register via
RegisterWebhook when a subscribed chokepoint’s disruption score is at or
above your alertThreshold (and its live signals above minLiveSignal
when set), once per crossing, including one already in progress at
first evaluation. It re-arms below the threshold unless a score input
missing since the last delivery could explain the drop. Failures retry
every 5 minutes with the same X-WM-Delivery-Id while the score holds;
5 failed ticks deactivate the webhook. Full rules at
https://www.worldmonitor.app/docs/api-shipping-v2#delivery-worker.
Verify X-WM-Signature-V2 in constant time against
sha256= + hex(HMAC-SHA256(key=secret,
message=timestamp.deliveryId.event.rawRequestBody)). Use the exact
header strings and raw body bytes. Use secret verbatim;
do not hex-decode it or re-serialize JSON. Reject missing or malformed
headers and timestamps more than 300 seconds in the past or future.
Require V2; never fall back to the legacy body-only signature.
Atomically dedupe verified delivery ids for the subscription lifetime.
Retries keep the id but refresh the timestamp and signature.
Respond with any 2xx to acknowledge receipt.
{
"subscriberId": "wh_1a2b3c4d5e6f7a8b9c0d1e2f",
"chokepointId": "suez",
"score": 72,
"alertThreshold": 50,
"triggeredAt": "2026-07-04T12:34:56Z",
"reason": "navigational_warning"
}Headers
Legacy body-only HMAC-SHA256. No replay protection. Migrate to V2.
^sha256=[0-9a-f]{64}$"sha256=2b8c0d3e4f5a6b7c8d9e0f1a2b3c4d5e6f7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c"
HMAC-SHA256(secret, timestamp.deliveryId.event.rawRequestBody).
^sha256=[0-9a-f]{64}$Send time in Unix seconds. Accept within 300 seconds of the receiver clock.
^[0-9]+$Always chokepoint.disruption for this body. The other events
(country.risk_surge, news.breaking, market.move, natural.hazard) send the
same headers and signature with the payloads documented at
https://www.worldmonitor.app/docs/api-shipping-v2#delivery-format.
chokepoint.disruption Unique delivery identifier (whd_ + 32 hex chars). Use it to
dedupe retries and process deliveries idempotently.
^whd_[0-9a-f]{32}$"whd_1a2b3c4d5e6f7a8b9c0d1e2f3a4b5c6d"
Body
The wh_-prefixed subscription receiving this alert.
Chokepoint that breached the threshold (e.g. suez).
Current disruption score of the chokepoint, 0-100.
The subscription's configured alert threshold, 0-100.
ISO-8601 timestamp when the alert fired.
First matching rule in this order; score_threshold when none matches.
ais_congestion_spike, navigational_warning, transit_drop, score_threshold Name, status, warning and AIS counts, congestion, war-risk tier, transit change, previous score, feed time.
Response
Any 2xx acknowledges receipt. A non-2xx response or a delivery timeout marks the delivery failed.
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