Commands hang indefinitely when IHV execution providers are not installed

[anatarnousk]

Description

Several WinML CLI commands hang indefinitely when IHV-specific execution providers (e.g., OpenVINO for Intel NPU) are not installed. There is no timeout, error message, or user-facing warning — the CLI just freezes, requiring a manual kill.

Steps to Reproduce

1. Set up WinML CLI v0.1.0 on a system with an Intel NPU but without the OpenVINO EP installed

2. Run winml sys — the command prints system info but then hangs and never returns

3. Run winml analyze -m <model> — same behavior, the command hangs indefinitely

Expected Behavior

• Commands should detect missing EPs and either skip them gracefully or print a clear warning (e.g., ⚠ OpenVINOExecutionProvider not found — install the OpenVINO EP to use Intel NPU)

• Commands should time out rather than hang indefinitely if an EP probe is unresponsive

• winml sys --list-ep should indicate which EPs are installed vs. missing, so users can diagnose the issue before running pipeline commands

Actual Behavior

Commands hang with no output, no error, and no way to know the cause without prior knowledge that IHV EPs need to be installed separately.

Environment

• WinML CLI version: 0.1.0

• OS: Windows 11 (x64)

• CPU: Intel Core Ultra 7 268V

• NPU: Intel AI Boost (Driver: 32.0.100.4297)

• GPU: Intel Arc 140V (Driver: 32.0.101.6737)

• Python: 3.11.9

• onnxruntime: 1.24.5 (windowsml)

Suggestion

1. Add a timeout to EP probe/initialization calls so they fail fast instead of hanging

2. Surface a user-friendly warning when an EP is detected as available hardware but the corresponding provider package is not installed

3. Document which EP packages are required per device in the README prerequisites table (e.g., "Intel NPU requires OpenVINO EP — install via ...")

[xieofxie]

We have an issue tracking the downloading issue #725
We may need to revisit when the downloading should be triggered

[xieofxie]

Create the issue for proactively download when only needed #791
It needs more design discussion, so it will not be covered in resolving this issue

[DingmaomaoBJTU]

Triage Summary (2026-06-06)

Priority: P0 (confirmed — user-blocking hang with no workaround)
Component: CLI core / EP initialization
Assigned: @tezheng @xieofxie
Classification: Bug — Reliability

Analysis: Commands hang indefinitely when IHV EPs are not installed. This is a blocking UX issue — users cannot diagnose the problem without external knowledge. Requires timeout + graceful fallback on EP probe failure.

Action Items:

1. Add timeout to EP probe/init calls (fail fast after ~5s)
2. Surface clear warning when EP hardware detected but provider package missing
3. Document required EP packages per device in README

Target: Next release (P0 — fix before public preview)

[xieofxie]

With this pr #788, we now shows progress bar and could timeout when hangs, so close this