Direct answer: A green Director or Azure workbook is control-plane health, not end-user availability. CitraTest APM® is Tevron's continuous glass-level application performance and availability product. It drives real client paths on Citrix, Microsoft RDS, Azure Virtual Desktop, and thick Windows desktops; WaitForImage times what appears on screen; Publish -> Scenario -> SLA keeps the fleet on a schedule. No CitraTest agents on production session hosts for the glass path.

Director is green. The Azure workbook looks calm. Gateway returns 200 OK. And the clinician is still watching a spinner where the Epic chart should be.

That is not a mysterious outage. It is a category error in how many teams define "availability." Control-plane health answers whether brokers, gateways, and session hosts are alive. End-user availability answers whether the business screen appeared on the glass - login-to-shell complete, FSLogix profile attached, published app first paint done, chart or order line ready - in time for the people who do the work.

Citrix Virtual Apps and Desktops, Citrix DaaS, Microsoft RDS, Azure Virtual Desktop, and thick Windows clients still deliver pixels. HDX and RDP paint a desktop. If your monitoring stack never drives that desktop the way a person does - and never times what appears on screen - you can stay green while the shift falls behind.

Illustrative / method diagram - not Tevron customer results. Director and Azure remain useful for brokers and hosts; glass APM times the screen.

What glass-level APM means

CitraTest APM is Tevron's continuous application performance and availability product for this class of problem. Per the CitraTest User Guide and Quick Start, the measurement model is visual and non-invasive:

1. Scripts encode a real end-user workflow on a Windows desktop.
2. Playback sees the UI with bitmap images and OCR.
3. Playback acts with real mouse and keyboard input - the same path a person takes.
4. WaitForImage (and related waits) synchronizes and verifies that the expected screen state is true before the next step.
5. StartTimer / StopTimer capture true on-screen response: place StartTimer immediately after the initiating action; StopTimer immediately after WaitForImage confirms completion.

Nothing invasive is required on session hosts or application servers for the glass path itself. Tevron's APM positioning is explicit: no CitraTest agents on the production session hosts - only access from Windows to the target application (Citrix client, RDS/AVD client, thick client, browser, Epic/Cerner workspace, and more).

Illustrative method diagram - not customer results. That pipeline is the operational definition of on-the-glass synthetic APM.

Glass-level APM is therefore not "another protocol counter." It is a continuous synthetic that answers: did the user's moment of truth appear on screen within the SLA?

Related: What is on-the-glass APM?, What is CitraTest APM?, APM based on real user experience.

APM Web Console path: Publish -> Scenario -> Dashboard / SLA

Building the script is half the story. Operations needs a fleet path. The CitraTest Quick Start (Rev 46.7.7.2026) describes the APM Web Console integration as:

Availability for summary reporting is driven by successful iterations (Monitor Required Availability), separate from response-time bands. Screenshots on failure give ops on-glass proof instead of another abstract counter.

Illustrative fleet flow based on the Quick Start APM Web Console chapter - not customer results.

That is the continuous watch: same visual script, scheduled across PoPs, scored against SLA limits your business actually cares about - login-to-shell, open chart, submit claim, not merely "Gateway responded."

Coverage: one visual technology

Because CitraTest matches what is on the desktop, the same scripting model covers delivery paths that otherwise force tool sprawl:

• Citrix (CVAD / DaaS) and published apps
• Microsoft RDS
• Azure Virtual Desktop
• Thick Windows clients
• Web / any browser
• Clinical systems where the chart must appear on glass - Epic (including Hyperdrive on Citrix or AVD) and Cerner

A Workspace or AVD URL check is not an EHR test. The chart in Hyperspace or Hyperdrive has to paint. Win11 and Server 2025 endpoint positioning fits the same glass contract: standardize what the playback desktop sees, then measure it.

Illustrative coverage matrix - not a performance result. One visual technology; no host-side CitraTest agents for the glass path.

Related: Citrix & RDS APM, Epic EHR on-the-glass, HDX vs real user experience.

Display contract / reliability

Visual matching is honest only when display properties are part of the contract. Color depth, resolution, Appearance theme, font smoothing, and ClearType should match between the machine that captured baseline images and the machines that play them back - or you will chase false "image not found" failures that are really environment drift.

When you cannot fully standardize, the User Guide offers practical escapes: Relearn Mode (Image.0.bmp siblings), per-configuration image folders, and advanced match flags (color tolerance, percentage error). Keep images small and unique; mask regions that legitimately change (dates, edit-box contents). Prefer a static bitmap over OCR when the text never changes; reserve OCR for runtime values.

Reliability practices for APM fleets also include publishing cleanup scripts as standalone monitors, using script versioning for phased rollout (do not assign conflicting versions of the same script to one agent), and restoring a clean desktop between iterations so the next scheduled run starts honest.

Size with VU, watch the same path in APM

Lab and production answer different questions with the same glass definition of success.

• CitraTest VU sizes capacity: login storm vs density/sustain under concurrent load, from the glass.
• CitraTest APM watches the same path continuously: is today's login-to-shell and open-chart still inside the SLA?

Size the SKU in the lab. Watch the glass every shift. Existing APM hosts can serve as VU measurement machines when that is how you operate; the visual approach stays consistent either way.

Related products

APM remains the continuous application performance / availability layer: publish, schedule, SLA, alert.

Illustrative method diagram - not customer results. Geo bars are example scenario shapes, not Tevron benchmarks.

FAQ

Why can Director be green while users still wait?
Director and Azure workbooks report control-plane and host health. They do not time whether login-to-shell, FSLogix attach, published-app first paint, or an Epic/Cerner chart appeared on the glass.

What does CitraTest APM measure on the glass?
Scripts drive real mouse and keyboard; WaitForImage verifies screen state; StartTimer/StopTimer capture on-screen response for login-to-shell, first paint, and in-session steps.

Do you need agents on production session hosts?
No. For the glass path, CitraTest APM does not require agents on production session hosts - only Windows access to the target client path.

How does Publish to Scenario to SLA work?
Publish Script sends the exe and images to the APM Web Console; Scenarios schedule Groups and Monitors; Agents play them back; dashboards score up to four SLA response-time limits per Monitor/Timer.

How does CitraTest APM relate to CitraTest VU?
VU sizes capacity under concurrency from the glass. APM watches the same path continuously against production SLAs.

If your Director is green and your users are not, measure the desktop. Product page: Application Performance Monitoring - CitraTest APM.

Citrix, Director, HDX, ICA, StoreFront, Workspace, Microsoft, Remote Desktop Services, Azure Virtual Desktop, Epic, Cerner, Oracle Health, and related marks are trademarks of their respective owners. Tevron is not affiliated with Citrix, Microsoft, Epic, or Cerner. Names are used for identification only. CitraTest APM® and CitraTest VU® are Tevron products.