Response text missing from stdout in -p (non-interactive) mode; only stats are written

[polajenko]

Bug Report

Description

When using copilot -p (non-interactive/programmatic mode), the assistant's response text is never written to stdout. Only the stats footer and extension notifications appear. The response is rendered to the TUI/alt-screen buffer instead, making it impossible to capture via piping or redirection.

Steps to Reproduce

copilot -p "what is 1+1?" --yolo

Expected Output

2

Actual Output

⚡ Aegis extension loaded (with dashboard)

Changes    +0 -0
Requests   1 Premium (10s)
Tokens     ↑ 29.9k (11.0k cached) • ↓ 5

The response content (2) is completely absent from stdout. Confirmed by capturing raw bytes — no response text present at all.

Also Tested

• --yolo -s → empty output (silent flag also broken)
• --allow-all-tools → same issue
• --screen-reader → same issue
• --no-custom-instructions → same issue
• --no-color → same issue

Workaround

--output-format json works and the response can be parsed from assistant.message events:

copilot -p "what is 1+1?" --yolo --output-format json |
  ForEach-Object { try { $_ | ConvertFrom-Json } catch {} } |
  Where-Object { $_.type -eq "assistant.message" } |
  ForEach-Object { $_.data.content }

Environment

• CLI Version: 1.0.54
• OS: Windows (PowerShell)
• The -p flag is documented as supporting scripting use cases, so this is a blocking issue for automation.

[polajenko]

Duplicate of #3188.