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200-901 Cisco Platforms and Development Practice Question

A developer is building an application that interacts with the Webex API to create rooms and send messages. The application needs to receive real-time notifications when a new message is posted in any room. Which TWO actions should the developer take? (Choose two.)

⚠ Common exam trap

200-901 often tests the difference between polling and webhooks; candidates may choose polling for simplicity, but the question asks for real-time notifications, which requires webhooks.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Provide a target URL where the webhook sends the notification

Option B is correct because Webex webhooks require the developer to supply a targetUrl — an HTTPS endpoint on their own publicly reachable service — where Webex will POST the notification payload when the subscribed event fires. Option D is correct because real-time notification of a new message is delivered by registering a webhook whose event is 'created' and whose resource is 'messages' (i.e., message.created), which is exactly the trigger Webex uses for newly posted messages. Option A is wrong because polling GET /v1/messages every second is inefficient, rate-limit prone, and not a real-time push mechanism. Option C is wrong because roomId is a filter/query parameter for listing messages, not a mechanism for receiving notifications. Option E is wrong because 'seen' is not a valid message event for this purpose and the payload described does not register a message-created subscription.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
Poll the GET /v1/messages endpoint every second
Why it's wrong here
Polling GET /v1/messages every second is pull-based, introduces latency and rate-limit risk, and cannot deliver the real-time push notifications required. Polling is the correct approach only where webhooks are unavailable or the API offers no event subscription mechanism.
✓
Provide a target URL where the webhook sends the notification
Why this is correct
A webhook requires a reachable HTTPS target URL, because Webex POSTs each event payload to that endpoint rather than the app polling. Supplying it satisfies the real-time notification requirement, since without a registered target the subscription cannot deliver anything.
✗
Use the 'roomId' parameter to filter messages
Why it's wrong here
Filtering by roomId narrows which rooms trigger notifications, but the requirement is notifications for any room, so this parameter contradicts the scenario. It is genuinely useful when a webhook should fire only for a specific room's messages, which is the opposite of what is asked here.
✓
Register a webhook for the 'message.created' event
Why this is correct
Registering a webhook for the 'message.created' event satisfies the real-time notification constraint: Webex pushes an HTTP POST to your callback URL the instant a message is posted, rather than requiring polling. This delivers event-driven updates across all rooms the authenticated user can access.
✗
Send a POST request to /v1/webhooks with 'resource: messages' and 'event: seen'
Why it's wrong here
The 'seen' event fires when a message is read, not when it is posted, so it cannot signal a new message. Registering a webhook with resource messages and event created is correct; 'seen' suits read-receipt tracking instead.

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200-901 Cisco Platforms and Development Practice Question

Why each option matters

Option-by-option breakdown

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