`aspire agent init` does not detect portable GitHub Copilot AppImage installations

[ellahathaway]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

On Linux, aspire agent init cannot detect an App-only GitHub Copilot installation when the official AppImage is launched directly without desktop integration.

GitHub Copilot App detection currently relies on either:

• AI_AGENT=github_copilot_app_agent, available while running inside an App session; or
• a GitHub Copilot .desktop entry in an XDG applications directory.

A directly launched AppImage does not necessarily install a .desktop entry, and a normal terminal does not inherit the App runtime marker. In that case, if Copilot CLI is also absent, aspire agent init does not detect Copilot and skips the shared MCP, skills, and telemetry-hook configuration.

Expected Behavior

App-only Linux users should have a supported way for aspire agent init to recognize or explicitly select their GitHub Copilot installation outside an active App session.

If the App creates a reliable persistent marker, Aspire should use it. Otherwise, consider an explicit configuration/override mechanism and document the portable-AppImage limitation rather than scanning arbitrary filesystem locations.

Steps To Reproduce

1. Download and run the official GitHub Copilot AppImage on Linux without installing a .desktop entry.
2. Ensure the standalone Copilot CLI is not installed.
3. Open a normal terminal where AI_AGENT and COPILOT_CLI are unset.
4. Run aspire agent init.
5. Observe that GitHub Copilot App is not detected and shared Copilot configuration is skipped.

Exceptions (if any)

N/A

Aspire doctor output

N/A — this is an installation-discovery limitation rather than a missing Aspire prerequisite.

Anything else?

This limitation was identified while testing #19820:

• Detection concern: Detect GitHub Copilot App as an agent client #19820 (comment)
• Reproduction report: Detect GitHub Copilot App as an agent client #19820 (comment)
• The PR was approved with this limitation accepted for follow-up: Detect GitHub Copilot App as an agent client #19820 (review)

Users who also have Copilot CLI installed are unaffected because the shared Copilot configuration is applied through CLI detection.

[joperezr]

🤖 Aspire triage pass — 2026-09-02 17:04 UTC

Area: area-cli
Kind: bug
Repro: yes-minimal — see lines 26–30 of the issue body
Affected version(s): not stated (latest: 13.5.3)
Severity: S3 — portable Linux installation discovery is skipped, but desktop integration or the standalone CLI provides a workaround

Urgency: ⚪ backlog — no milestone
Reason: valid edge-scenario bug with a workaround, but not important or actionable enough for 13.6

Suggested owner(s): James Newton-King (@JamesNK) (score 243), backup Adam Ratzman (@adamint) (score 140)
Evidence:

• JamesNK merged Remove flaky duplicate child log path test #19538, Color statuses in aspire ps output #19369, Preserve CLI status messages without interactive spinners #19272 in area-cli (last 90d)
• JamesNK closed [main] aspire doctor taking 15 secs to run #19016, Use resolved dotnet paths in aspire doctor #19003, [13.5] Trace logging on aspire doctor causes weird indentation #19017 as completed in area-cli
• adamint merged Bound AppHost auxiliary backchannel handshake #19832, Fix Java starter JDK and transport reliability #19635, Make CLI resource observation reusable #19567 in area-cli (last 90d)

Confidence: medium
Needs human?: no