The city wants to enable a new summarizer prompt version citywide without redeploying every service. Where should the toggle live?
Select an answer to reveal the explanation.
Short Explanation
Feature flags are the citywide light switch in App Configuration—flip once and parks, permits, and 311 all see the new summarizer path.
Full Explanation
To enable a new summarizer prompt version citywide without redeploying every service, store a feature flag (or configuration key) in Azure App Configuration that each generative service evaluates before selecting the prompt version. App Configuration centralizes the toggle, supports labels per environment, and—when dynamic refresh is enabled—lets parks, permits, and 311 assistants flip to the new summarizer path on a controlled rollout without rebuilding Container Apps or Functions. Feature flags also support gradual exposure and quick rollback if the new prompt regresses civic answers.
Rebuilding and redeploying every Container App image whenever the prompt version changes fails the no-redeploy goal: image rebuilds are slow, couple content changes to release trains, and increase blast radius for a configuration decision. Hardcoding the prompt version inside each service binary with no central toggle fails consistency—different municipal services drift to different versions, and rollback requires another code change. Changing DNS records alone to switch prompt versions with no configuration service fails conceptually: DNS points to hosts, not prompt templates, and cannot express percentage rollouts or per-app evaluation logic for summarizer selection.
Exam caveat: App Configuration feature flags are for non-secret behavioral switches; do not place model API keys in App Configuration. Pair flags with refresh intervals or sentinel keys so running processes actually see the flip. Also separate ‘config change’ from ‘model deployment’—a prompt version flag does not replace validating the new prompt against municipal content-safety and groundedness checks.
Operational check: set the summarizer flag for a staging label first, confirm services select the new version without redeploy, enable production gradually, monitor summarizer quality and error rates, then flip the flag off to prove rollback without image rebuilds.