Bug: Voice mode cannot be enabled - Failed to fetch model catalog (catalog unreachable on corporate VPN)

[MrRishabhJain]

Bug: Cannot enable voice mode — "Failed to fetch model catalog" / "Couldn''t load voice model catalog"

Summary

Activating voice mode with /voice fails because the CLI cannot fetch the voice (STT) model catalog. Voice mode can''t be enabled at all, since the catalog must be reachable before any speech-to-text model can be downloaded.

What I see

Two dialogs appear when trying to enable voice mode:

1) Voice models picker:

Voice models

No STT models available.
Your CLI may be out of date. Run /update to update, or download from:
https://github.com/github/copilot-cli/releases

Failed to fetch model catalog. Press r to retry.

2) Blocking dialog:

Couldn''t load voice model catalog
The voice model catalog couldn''t be fetched.

Voice mode can''t be enabled until the catalog is reachable. Check your network connection and retry.

> Retry
  Cancel

Pressing r / Retry does not resolve it — the catalog still fails to load and no STT models become available, so voice mode never enables.

Steps to reproduce

1. Run the Copilot CLI.
2. Invoke /voice to enable voice mode (dictation transcription via Foundry Local).
3. The CLI attempts to fetch the voice model catalog and fails with the errors above.

Environment

• OS: Windows 11 (arm64)
• Copilot CLI version: 1.0.57
• Network: corporate environment. The machine was connected to a corporate VPN (Azure VPN). The failure occurs in this restricted-network context, which strongly suggests the model-catalog / model-download endpoints are being blocked by the VPN/proxy/firewall.

Expected behavior

• Voice mode should be able to fetch the model catalog and download STT models in corporate/proxy/VPN environments, OR
• The error should clearly identify the exact endpoint(s) it''s trying to reach (host/URL) and respect system/HTTP(S) proxy settings, so the URLs can be allow-listed.

Impact

Voice mode is completely unusable in restricted-network/VPN environments because the catalog fetch is a hard prerequisite and there is no offline / manual model-install fallback surfaced in the UI.

Suggested improvements

• Surface the exact catalog/model URLs in the error so they can be allow-listed.
• Honor HTTPS_PROXY / system proxy and custom CA settings for the catalog + model download.
• Provide an offline / manual model-install path when the catalog is unreachable.

Screenshots

[MrRishabhJain]

Adding the two screenshots showing the voice-mode activation failure:

1) Voice models picker — "No STT models available / Failed to fetch model catalog":

2) Blocking dialog — "Couldn't load voice model catalog":