Vercel has enhanced its observability platform by integrating external API caching insights, enabling developers to track how many requests to third-party APIs are served from the Vercel Data Cache versus being routed to the origin server. As of May 22, 2025, users can view caching behavior at the hostname level, with those on Observability Plus gaining more granular path-level metrics in the dashboard.
Vercel’s Data Cache is a specialized layer designed to work with frameworks like Next.js, storing fetch responses per region with support for time-based and tag-based invalidation. By exposing cache hit data, Vercel helps teams pinpoint areas where they can further leverage caching to reduce latency, decrease origin requests, and enhance application performance.
This feature builds on the broader rollout of “Observability”, initially launched in beta in October 2024 and generally available since December, which offers comprehensive insights into function invocations, edge requests, build diagnostics, and external API calls. The addition aligns with Vercel’s focus on visibility and performance for frontend and serverless workloads.
On Vercel’s official changelog account, they highlighted that their CDN now “caches proxied responses using the CDN-Cache-Control and Vercel-CDN-Cache-Control headers”, an essential precursor to deeper caching analytics in Observability.
Developers interested in using this feature can visit the External APIs tab in the Observability dashboard to view cache hit metrics for deployed projects and evaluate opportunities for efficiency gains in API usage.
While Vercel’s native integration of external API caching metrics into its observability suite is a notable step forward, other companies also offer solutions, albeit often with more manual setup or third-party integrations. Netlify, for instance, supports caching strategies at the CDN level, but support for observability into external API calls often requires pairing with tools like New Relic, Datadog, or Grafana for custom dashboards and telemetry pipelines. These platforms can ingest logs and metrics from API calls; however, developers must manually configure them or do so via SDKs.
Cloudflare, meanwhile, offers advanced caching rules and Cache Analytics as part of its Enterprise plans. While it can show cache hit ratios and performance metrics, detailed visibility into external API usage typically requires correlating data from other sources, such as log push services or API gateways like Kong or Apigee, which can add operational overhead. Cloudflare Workers users can log external fetches, but the depth of insights depends on how comprehensively telemetry is captured.
AWS and Google Cloud offer more granular API Gateway and CDN logging, with services like Amazon CloudWatch, X-Ray, and Cloud Monitoring providing observability. Still, surfacing high-level caching insights across external APIs often requires stitching together telemetry from multiple services and instruments, unlike the streamlined integration Vercel now offers out of the box.
The key difference lies in developer experience: whereas traditional approaches require integration effort and expertise in observability tooling, Vercel bundles relevant metrics into the same surface where developers already monitor functions and deployments. This simplification could serve as a model for other developer-first platforms looking to unify caching, observability, and performance optimization into a cohesive experience.
