Used during initial app configuration. When you first configure your Request URL, Slack sends a url_verification challenge event. Your app must respond with the challenge value to confirm ownership.
URL verification challenge sent during Request URL configuration
Content-Type: application/json
About AsyncAPI
The AsyncAPI specification describes event-driven APIs the way OpenAPI describes request/response APIs. A channel is the named pipe — a webhook URL, a Kafka topic, a WebSocket route, an MQTT subject — that producers and consumers publish or subscribe to. Each channel carries one or more messages with structured payloads, and an operation declares whether a given party sends or receives on that channel.
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